Wednesday, January 28, 2009

Green Tea Catechin Reverses the Effect of DHT in Prostate Cancer Cells

Green tea works synergistically with DHT in cancer cells
Green tea works synergistically with DHT in cancer cells. (Photo by Roshans Album)

When it comes to cancer-related deaths in men, prostate cancer is topped only by lung cancer, which is the number one leading cause of cancer deaths in both sexes. Cancer itself is second only to heart disease in death rates.

Green tea's anti-cancer effects are well known by now, but it's not always clear how exactly green tea works against different types cancer. In most cases, the reason behind the health benefits is one of the catechins of green tea – epigallocatechin gallate (EGCG), to be precise.

The same is apparently true with prostate cancer as well. Thomas et al. studied the effect of EGCG on different cell lines involved in prostate cancer. They found that green tea induced death in prostate cancer cells. In addition, when dihydrotestosterone (DHT) was present, the effect was even greater.

Androgens and prostate cancer

DHT is an androgen, which is a generic term for compounds that stimulate or control the development of male charasteristics. Androgens are also a key element in regulating prostate growth. That's why androgen withdrawal is used as a treatment for prostate cancer.

However, once the cancer develops past a certain stage, anti-androgen therapy stops working. The cancer then turns to other ways of growing, one of which is insulin-like growth factor (IGF-1). This makes treating prostate cancer challenging.

Green tea and prostate cancer

In the study, EGCG decreased the proliferation of both the androgen-sensitive and androgen-insensitive prostate cancer cells. The effect was dose-dependent. At the highest dose, the proliferation of the androgen-insensitive cells was decreased by 88.2% and 87.5%. Androgen-sensitive cell proliferation was cut by 59.7%.

With smaller doses, EGCG had only an anti-proliferative effect, whereas higher doses caused actual cell death in the cancer cells. The amount of dead cancer cells more than doubled with the larger doses.

DHT, green tea and prostate cancer

When DHT was added to the androgen-sensitive cells, the growth of cancer cells increased dose-dependently at first. However, after the amount of DHT passed a certain point, the proliferation began to decrease. At the second largest dose, proliferation had decreased below the control cells, and at the largest dose it was almost completely stopped.

When both DHT and ECGC were used on androgen-sensitive cells, cancer cell growth was reduced more than when using only DHT or ECGC. This means DHT and ECGC somehow work together to produce an anti-cancer effect.

The authors also note that in the presence of DHT, the cells became sensitized to EGCG, so that a dose of EGCG that normally wouldn't cause cell death now caused it. IGF-1, on the other hand, did not have this sensitizing effect.


Green tea and its main polyphenol, EGCG, is effective in inhibiting prostate cancer cell growth. This anti-cancer effect is seen regardless of whether the cancer cell line is sensitive to androgens or not. In the presence of DHT, green tea becomes more effective.

For more information on green tea, see these posts:

Caffeine and Polyphenol Contents of Green Tea, Black Tea, Oolong Tea & Pu-erh Tea
How Black Pepper Increases the Bioavailability of the Healthiest Green Tea Catechin
Drinking 10 Cups of Green Tea Daily and Not Smoking Could Add 12 Years to Your Life
Green Tea, Black Tea & Oolong Tea Increase Insulin Activity by More than 1500%

Read More......

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Monday, January 26, 2009

Anti-Aging in the Media: 60 Minutes on Resveratrol

Red grapes are one of the natural sources of resveratrol.

Looks like 60 Minutes and CBS have jumped on the anti-aging bandwagon. The piece is mostly about resveratrol, the famous compound found especially in red wine.

Resveratrol and its possible longevity benefits are nothing new of course, but it's good to see such a popular show feature it in a positive light. Here's a quote from the article, which is basically a transcription of the video:

Resveratrol has been tested on mice and the results have been encouraging. In a test-video provided by Sirtris, two mice were fed a high fat diet for 12 weeks. But when placed on a treadmill, one of the mice ran twice as far. He was given high concentrations of resveratrol.

"You have fat mice, and you have fat mice with resveratrol. And the ones that are on resveratrol, they can run twice as far, and they live longer, about 20 percent longer," Sinclair says.

Other studies showed that among mice fed a high fat diet, those taking resveratrol didn't gain as much weight as those not given the drug. Sinclair believes that resveratrol actually changes the physiology of the mice.

The proof, he says, is in the post-mortems. "Their organs looked pristine, youthful, fat-free, and their physiology was just like they were dieting. But they were fat."

As for effects on humans, Sinclair (who launched the biotech company Sirtris with Dr. Westphal) comments:

"We're talking about is potentially making a 90-year-old as healthy as a 60-year-old. A 90-year-old can play tennis, and see their great grandkids graduate from college. People will live active, healthy lives and then die quietly in their sleep. And that's really the aim here with these medicines."

I agree that this may be a first step in the right direction, but I hardly think dying in your sleep is the best possible end result. Instead, the short term goal is to develop drugs that keep us healthy until old age; the long term goal is to use those extra years to develop better and more effective drugs. The ultimate goal should be to not die at all.

Still, it's understandable that Sirtris is cautious about what kind of claims they make. Even though I'm fairly sure Dr. Sinclair and Dr. Westphal are mostly interested in the longevity benefits of resveratrol, their products are marketed as drugs against diseases like diabetes. It's much easier to get FDA approval for a diabetes drug than it is for a life extension drug, and now that GlaxoSmithKline bought Sirtris (for almost three quarters of a billion dollars), I'm sure they'll be even more careful about how they market their product.

No story on anti-aging would be complete without mentioning caloric restriction and a mandatory joke about CR practicers who "may not live longer, but it'll sure feel like it". That one just keeps getting funnier every time, doesn't it? But to 60 Minutes' credit, the CR Society's "low-calorie happy hour" featuring baby food and tomato juice doesn't exactly seem like the party of a lifetime.

So when is this stuff ready to be popped in pill form? Here's an estimate straight from the horse's mouth:

"I would say five years to be conservative that this'll happen within our lifetimes. I'm fairly certain about that," Sinclair says.

I'm not sure what exactly the folks at Sirtris are up to with their formulation, but resveratrol is and has been available for quite some time now from several manufacturers, even in highly concentrated forms. It's not cheap, but if you want to give it a go, it won't cost you an arm and a leg either.

For more information on anti-aging, see these posts:

Anti-Aging in the Media: Newsweek on the Search for Longer Life
End Aging to End Anxiety: Filmmaker Jason Silva Talks about Immortality
Growing New Body Parts: Breakthroughs in Regenerative Medicine
Drinking 10 Cups of Green Tea Daily and Not Smoking Could Add 12 Years to Your Life

Read More......

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Saturday, January 24, 2009

Chinese Hibiscus Leaf Extract Increases Hair Growth in Mice

Hibiscus rosa-sinensis is traditionally used as a hair growth remedy. (Photo by williamnyk)

Hibiscus rosa-sinensis, also known as Chinese hibiscus or China rose, is cultivated as an ornamental plant throughout the tropics. The flowers of the plant are edible and can be added to salads. Preparations made from the flowers are also reputed to have medicinal properties.

One of these properties is increasing hair growth, which is why a lot of hair growth products in India include extracts of Hibiscus rosa-sinensis. It is also said to help prevent greying hair.

The study

Much of the claims are based on tradition and anecdotal evidence instead of scientific studies. In a rather rare study, Adhirajan et al. tested the effects of two Hibiscus rosa-sinensis extracts, one made from leaves and one from flowers, on albino rats.

The extract was made by drying and powdering leaves and flowers of the plant, extracting them with petroleum ether and then mixing a gram of the extract in 100 ml of liquid paraffin. This produced the 1% active compound, which was topically applied on the backs of shaved mice.


No difference in the number of hair follicles was observed between the treated and control groups. Thus, the extract didn't grow any new hairs.

However, the hair growth cycles of the rats treated with the extract were significantly different from those in the control group. After 30 days, the anagen/telogen ratio of hair follicles was 50/50 in the control group, 54/46 in the placebo group, 60/40 in the flower extract group, and 67/33 in the leaf extract group.

Hair growth with Hibiscus rosa-sinensis in Albino mice: effect on hair growth cycle
In other words, after a month of applying the leaf extract, 67% of the hair follicles were in the anagen (growth) phase, whereas in the control group only 50% were in the anagen phase.

The length of hair was also higher in the treated rats. After 30 days, the average length of hair in millimeters was 13.6 in the control group, 14.5 in the placebo group, 15.8 in the flower extract group, and 17.0 in the leaf extract group.

Hair growth with Hibiscus rosa-sinensis in Albino mice: effect on hair length
Looking at the graph, the effect on hair length doesn't seem as dramatic as the effect on hair growth cycles. Still, compared to the control group, the leaf extract group showed a 25% increase in hair length, which isn't bad at all. Hair follicle length was also significantly increased the leaf extract group in vitro.

Hair growth with Hibiscus rosa-sinensis in Albino miceHair growth in shaved mice: control vs Hibiscus.

The above picture shows an initially shaved albino rat (e), a control group rat after 30 days (f), and a rat treated with leaf extract after 30 days (g).


The leaf extract of Hibiscus rosa-sinensis increases hair length and the anagen/telogen ratio of hair follicles in mice. The flower extract showed similar but more modest increases. Therefore, extracts made from the leaves of the plant are a possible hair growth remedy.

For more information on hair growth, see these posts:

How I Accidentally Grew Hair on My Left Temple with Retinol
Mixture of 5-Aminolevulinic Acid and Iron Increases Hair Growth in Mice
Vitamin E Tocotrienols May Grow Hair in Humans
Green Tea Extract Grows Hair in Vitro, Might Work in Vivo

Read More......

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Monday, January 19, 2009

Caffeine and Polyphenol Contents of Green Tea, Black Tea, Oolong Tea & Pu-erh Tea

Workers making pu-erh tea. (Photo by zgware)

If you've ever wondered about the polyphenol and caffeine content of different types of tea, this post is for you.

The data in the following figures is by Kuo et al. who compared the effects of green tea, black tea, oolong tea and pu-erh tea on rats. I'll review the rest of the paper later and just present the polyphenol content of various teas in this post.

The first graph has all four tea varieties, major catechins (the most biologically active group of tea polyphenols) and caffeine content listed. The catechins are epigallocatechin (EGC), epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epicatechin (EC), gallocatechin (GC) and catechin (C).

Polyphenol content of various tea
EGCG and EGC are clearly the most abundant catechins. Green tea takes the cake with the highest amount of both. None of the other three come even close to green tea's EGC content.

The second graph has green tea removed from it to give us a better look at how the rest of the teas fare.

Polyphenol content of various tea
Here oolong tea stands out with its high EGCG content. A lot of the studies on the health benefits of tea concentrate on EGCG, so oolong tea seems like a healthy choice too. It also has the least amount of caffeine along with green tea.

The third and last graph has EGCG and EGC removed to give a better view of the other catechins.

Polyphenol content of various tea
Green tea and oolong tea are the winners in the EC and ECG categories, but when it comes to GCG and plain old C, it's black tea that is number one.

Which tea is the healthiest?

Based on the figures above, the healthiest choice in terms of catechin content is green tea. Oolong tea comes in second. As you can see from the graphs, the more fermentation the tea has gone through, the less catechins it has.

Keep in mind, however, that not all of the health benefits of tea come from catechins. Thanks to the catechin-destroying fermentation process, black tea has more theaflavins, which have their own health effects. Remember also that these numbers are from one study only, so you shouldn't rely on them blindly.

What are oolong tea and pu-erh tea?

I'm sure you already know the difference between green tea and black tea, but what about oolong tea and pu-erh tea? Oolong tea is really just a mixture between green and black tea: whereas green tea has gone through minimal fermentation and black tea is fermented, the length of fermentation when producing oolong tea is somewhere in the middle.

Pu-erh tea, named after the region where it was first harvested, is traditionally made with leaves from old wild tea trees. Pu-erh is a post-fermented tea, which means it has undergone a period of aging in open air. The aging may take from months to years and makes pu-erh a highly sought-after tea.

For more information on tea and health, see these posts:

How Black Pepper Increases the Bioavailability of the Healthiest Green Tea Catechin
Drinking 10 Cups of Green Tea Daily and Not Smoking Could Add 12 Years to Your Life
Green Tea, Black Tea & Oolong Tea Increase Insulin Activity by More than 1500%
Black Tea is More Effective in Activating Superoxide Dismutase (SOD) than Green Tea

Read More......

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Sunday, January 18, 2009

Intermittent Fasting Improves Insulin Sensitivity Even without Weight Loss

The modern paleolithic man feasts, famines & burns shopping carts. (Photo by Misserion)

Though you may not have heard the term that often, insulin resistance is a big health problem these days.

What insulin resistance means in practice is that normal amounts of insulin are not enough to produce an insulin response – a signal for cells to take up glucose from the blood. The result of prolonged insulin resistance is diabetes, and everyone has heard of diabetes.

Since diabetes is really the end result of a long process (which has the ultimate end result of death), it's much easier and more economic to tackle insulin resistance before things get out of hand.

Several small meals or a few big ones?

The traditional wisdom says that the key to staying healthy, lean and fit is to eat several small meals a day. "Keep blood sugar levels constant" and "breakfast is the most important meal of the day" are the mantras recited often by the ever-working slaves of the food pyramid. The same people are often quick to remind you that not eating at least six loaves of bread each day will surely kill you.

But there are also different, non-conventional approaches to this problem. One of them is intermittent fasting, which I have been following for the past six months (click here for the latest update). It's based on the idea that the paleolithic man didn't have access to food all the time. Instead, he would go for long periods without food (hunting and gathering), and when food was available (after a succesful kill), he would eat a lot. Feast and famine.

In short, the intermittent fasting approach is the complete opposite to common wisdom, which you've undoubtedly been taught ever since you were on an all-milk diet.

So who is right – your mother who warned you not to go too long without eating, or those crazy blogger folks who want you to get in touch with your inner caveman? When it comes to insulin sensitivity, whose cuisine reigns supreme?

Intermittent fasting and insulin sensitivity

Lucky for us, there are scientists out there working day and night to answer these questions. Among them are Halberg et al., who subscribe to the paleolithic feast and famine theory in their paper. They studied the effect of intermittent fasting on insulin action in eight young and healthy Caucasian men.

The participants were told to fast every second day for 20 hours. Each fasting period started at 10 PM and ended at 6 PM the following day. The study lasted for two weeks, giving a total of seven fasting periods. The subjects were told to eat as they normally would, except for two days before insulin measurements when they had to eat 250 grams of carbohydrates per day.

Body weight and body fat did not change during the experiment. Fasting (after an 8-hour overnight fast) plasma glucose and plasma insulin concentrations were also similar before and after the intermittent fasting experiment.

However, an increased insulin action on glucose uptake was noticed after the IF period. In other words, when the participants had gone through their two-week intermittent fasting experiment, their insulin was more effective in telling cells to take up glucose from blood. Increased inhibition of lipolysis, the breakdown of fat stored in fat cells, was also noticed.

Even though both of these – more glucose taken from blood and less breaking down of fat – may seem like negative things at first glance, they are important functions of insulin. An increase in these means improved insulin sensitivity. When insulin fails to do these things, that's when there's a problem.

After each 20-hour fasting period, the amount of circulating adiponectin was increased by 37% on average. Plasma adiponectin is positively correlated with insulin sensitivity, which explains the increased insulin action noticed after the IF period.


After two weeks of intermittent fasting, body weight, body fat percentage and muscle energy stores were unchanged in a group of eight healthy men. Insulin levels were unchanged, but insulin activity increased (a similar effect to that of green tea, black tea & oolong tea).

The fact that the participants lost no weight means that the improvement in insulin sensitivity is not due to a restriction in calories but the fasting periods themselves. This lends support to the idea that periodical fasting is beneficial for insulin sensitivity. Time to hear the inner caveman's call?

For more information on intermittent fasting and insulin, see these posts:

Intermittent Fasting with a Condensed Eating Window – Part I: Poorer Insulin Sensitivity and Glucose Tolerance?
A High-Protein Diet Is Better than a High-Carbohydrate Diet for Weight Loss
Intermittent Fasting: Understanding the Hunger Cycle
Green Tea Extract Increases Insulin Sensitivity & Fat Burning during Exercise

Read More......

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Saturday, January 17, 2009

How I Accidentally Grew Hair on My Left Temple with Retinol – Experiment Conclusion

Carrots contain the plant form of vitamin A. (Photo by John-Morgan)

This post is the rather surprising conclusion of my topical retinol experiment.

For the past six months, I've used retinol, a form of vitamin A, on the left side of my face. The idea was to see whether it improves fine wrinkles and increases collagen production like at least one study suggests.

I have to admit I haven't seen much in terms of skin quality during these six months. I don't really have wrinkles at this age, but the fine lines on my forehead and the small crow's feet next to my eyes are still there.

I don't doubt the quality of the product, however. Applying the cream on my face gives a slight tinge, and afterwards there is a small but notable peeling effect. This peeling effect is behind the effectiveness of stronger forms of vitamin A, like tretinoin. Retinol is not supposed to cause peeling, but at least the 2% cream I used seemed to do so.

The surprise is that I have grown a few new hairs on my left temple. Even though I have experimented with and reported on various substances that are supposed to grow hair, this experiment was not supposed to be about growing hair. It happened by accident.

I'm pretty sure my hairline has always been where it is now, and no hair has ever grown where these new hairs are suddenly sprouting up. I'm not sure yet whether they're vellus hairs or terminal hairs, but it seems they're still growing.

I attempted to capture the whole thing with a camera. The result is not that great, but you can see the areas where the 3-4 new hairs are growing from circled with red.

On the right temple where no retinol was applied, no new hair is growing, so I think it's safe to conclude that the hair growth effect is due to the retinol cream. If you've read the blog before, you know that this is not my usual conclusion (for examples, see the conclusions to my MSM experiment and biotin experiment).

As you can see, it's very modest: only a couple of new hairs are growing and you kind of have to zoom in to even see it. Still, I find the result interesting, since it proves that retinol is absorbed and does something to the skin. It's effect on wrinkles may be too small to notice, but it's effect on hair growth is visible.

Especially strange is that, as far as I know, this is not a part of the skin where hair used to grow and is now growing again, but a part of the skin where hair has never grown.

If you're bald, I doubt retinol cream alone will grow you a new set of hair. Nonetheless, I think these results warrant further studies on how different forms of vitamin A affect hair growth. I'm probably going to give tretinoin a go next to see whether the stronger stuff has a stronger effect.

I would like to see these results replicated in other people, so if you've tried retinol or tretinoin, do drop a comment and tell about your experience!

For more information on hair growth, see these posts:

1,000-8,000 mg of MSM Has No Effect on Hair & Nail Growth - Experiment Conclusion
Green Tea Extract Grows Hair in Vitro, May Work in Vivo
Nature's Hair Growth Medicines: Korean Red Ginseng vs. Tea Tree Oil
Vitamin E Tocotrienols May Grow Hair in Humans

Read More......

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Wednesday, January 14, 2009

How Black Pepper Increases the Bioavailability of the Healthiest Green Tea Catechin

How Black Pepper Increases the Bioavailability of the Healthiest Green Tea Catechin
A teaspoon of black pepper contains between 50-100 mg of piperine. (Photo by tokyofoodcast)

I've written quite a bit about green tea and its polyphenols on this blog. By now, it's pretty clear that they have a wide range of health benefits.

The one green tea polyphenol that seems to be especially healthy is epigallocatechin gallate (EGCg). It is one of the main catechins of green tea. Catechins are a type of flavonoids, which in turn are a a type of polyphenols.

As beneficial as EGCg is, it's not very well absorbed. In mice, the bioavailability is 26.5%; in rats, it's as low as 1.6%. We don't know how well humans absorb green tea catechins, but if these numbers are anything to go by, finding ways to improve the bioavailability seems like a good idea.

Fortunately, Lambert et al. have done just that. Apparently piperine, the black pepper alkaloid responsible for the pungent taste, increases the absorption in mice.

Black pepper has the ability to inhibit glucuronidation, which is a process that the body uses to make substances more water-soluble. This allows them to be eliminated from the body through urination. When this process is inhibited, it seems that the bioavailability of some substances is increased.

The important results from the study are listed below.

Piperine inhibits small intestinal glucuronidation. The small intestinal and hepatic microsomes of the mice glucuronidated EGCg rapidly. However, when piperine was administered with the catechin, glucuronidation in the small intestine was reduced by 40-60%, depending on the dose. The more piperine, the more inhibition.

Piperine and glucuronidation
The above figure shows that even the larger doses of piperine didn't have a significant on hepatic glucuronidation. On the other hand, small intestinal glucuronidation was significantly reduced.

Piperine increases plasma EGCg concentration. When piperine was administered to the mice along with epigallocatechin gallate, plasma levels of EGCg increased substantially.

Piperine and plasma levels of EGCG
The graph shows plasma levels of epigallocatechin gallate with and without piperine. The word "free" in the graph refers to unconjugated EGCg, while "total" refers to the total plasma level of EGCg. The bottom row of numbers represents time in minutes.

Piperine decreases excretion of EGCg. Another sign of better bioavailability with piperine is the fact that the mice administered both EGCg and piperine excreted less of the EGCg in their feces.

Piperine and absorption of EGCGAs you can see, here the effect of piperine is clear. Compared to the control group, the piperine group excreted less than half of the EGCg after 5 hours.

Implications for humans

As is usual with mouse studies and highly concentrated extracts, the amounts used and effects observed are not easily translated into human equivalents. The authors note that they used a 100% extract of EGCg, and that the amount of piperine used was about 40% of the EGCg amount (micromoles per kg).

One cup of green tea has about 180 mg of EGCg on average (the actual amount depends on quality and brewing time, among other things) and black pepper contains between 5-10% piperine.

If we take the cautious estimate of a 5% piperine content, then using the above-mentioned 40% number as is means that for each cup of green tea (containing 180 mg of EGCg), 1.44 g of black pepper (containing 72 mg of piperine) is needed. That's about one and a half teaspoon.

Keep in mind that this is a very rough calculation (and quite possibly even wrong). First, we don't know how well humans absorb EGCg. Even between mice and rats the differences were very big. Second, we don't know how much piperine affects the bioavailability of EGCg in humans. For now, we only know how it affects it in mice.


EGCg is perhaps the most important and healthy polyphenol of green tea. Though many studies have shown its benefits, the downside is EGCg is not well absorbed, at least not in rodents.

Piperine, a component of black pepper, increases the bioavailability of epigallocatechin gallate in mice. The more piperine was given, the more EGCg was found in plasma. Accordingly, the excretion of EGCg in feces was significantly reduced.

This improvement in bioavailability is likely due to piperine's ability to inhibit the glucuronidation of epigallocatechin gallate.
Piperine will likely improve the bioavailability of epigallocatechin gallate even in humans. The exact numbers, however, are a big unknown.

Still, don't let that keep you from adding a teaspoon of black pepper the next time you brew a cup of green tea.

For more information on green tea, see these posts:

Drinking 10 Cups of Green Tea Daily and Not Smoking Could Add 12 Years to Your Life
Green Tea, Black Tea & Oolong Tea Increase Insulin Activity by More than 1500%
Green Tea Grows Hair in Vitro, Might Work in Vivo
Green Tea Reduces the Formation of AGEs

Read More......

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Tuesday, January 13, 2009

Anti-Aging in the Media: Newsweek on the Search for Longer Life

Scientists are pushing life's autumn back. (Photo by prakhar)

I don't know if you've noticed, but there seems to be an anti-aging news story in the media almost every week these days.

In the past years, the tone of these articles and interviews has usually been quite negative. Scientists working in the field have often been dismissed as being unrealistically hopeful. Life extension has been seen as something of a fringe science.

Luckily, that trend is now changing. We're not only seeing more stories on how to prevent aging and live longer, we're seeing much more positive stories. That means life extension is seriously getting attention in mainstream media. As the science progresses, so do the attitudes.

A recent addition to anti-aging pieces appeared in Newsweek. In the article, the search for longer life is boldly declared "a real science" – something many journalists have not dared to say, probably out of fear of being ridiculed.

The author of the story also tackles common arguments against life extension:

Some critics of the scientific quest for longevity say it's God's will that we should die when our time comes. But in the past century, a clean water supply, antibiotics, vaccines and improved medical care have boosted life expectancy at birth by roughly 50 percent in the United States—from 48 for men and 51 for women in 1900 to 75 for men and 80 for women today. No one seems to object to that.

And of course, no article on how to live longer would be complete without mentioning caloric restriction. Even though several positive things about CR are pointed out, the conclusion is rather negative:

Extreme calorie restriction is not a practice that most people should try. Too many people are likely to simply yo-yo out of any initial weight loss. And pregnant women and children should never attempt it, lest they hinder development.

The last sentence might be true, but the yo-yo dieting argument doesn't really hold water. First, trying caloric restriction for a while and then returning to normal eating doesn't do any harm. In fact, it will probably do good, since intermittent fasting has shown many positive effects.

Second, any diet can be disputed by saying "Better not try it; I'd just put the weight back on". If this is true, how come so many people succeed on low-carb diets or paleolithic diets? I'm not saying caloric restriction is for most people (it isn't), but the argument against it in the article is not very strong.

Another thing that bugged me was a reference to the food pyramid, a terrible monument built by the worshippers of nutrition god Ancel Keys. His legacy is one we should get rid of once and for all. Here's the quote:

Studies are already yielding important clues on what produces healthy aging. One obvious answer is a healthy lifestyle, with plenty of exercise and a diet that includes lots of fruits, vegetables and whole grains. Seventh-day Adventists eat a vegetarian diet, don't smoke and spend a lot of time with family and church groups, which helps reduce stress.

The diet part is simply repeating the old mantra, even though the science does not back up the hypothesis that whole grains are really needed. I would be careful with fruit, too, since they contain lots of fructose, which may increase triglyceride levels.

I'm not convinced by the vegetarianism argument either: the Seventh-day Adventists also periodically fast, which may be the reason behind their longevity.

Still, I found the article an enjoyable read. Hopefully we'll see many more such stories during this year.

For more information on anti-aging, see these posts:

End Aging to End Anxiety: Filmmaker Jason Silva Talks about Immortality
Growing New Body Parts: Breakthroughs in Regenerative Medicine
Drinking 10 Cups of Green Tea Daily and Not Smoking Could Add 12 Years to Your Life
How the Accumulation of Minerals Might Cause Aging in Humans

Read More......

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Monday, January 12, 2009

The Effect of Maca Root on Energy and Libido – Experiment Conclusion

The Effect of Maca Root on Energy and Libido – Experiment Conclusion
The mighty Andes, home of maca root. (Photo by alvazer)

It's time to conclude my experiment with Peruvian maca root, the supposed health food of the Incas.

During the past month and a half, I have been consuming various amounts of powdered maca. The recommended amount on the label was one teaspoon, which is what I ate on most days. However, keeping with the inhuman spirit of the blog, I also experimented with bigger dosages on some days. The most I took was two tablespoons, about six times the recommended amount.

The nice thing about maca is that it doesn't taste too bad. At first, I mixed it with yoghurt, which made a decently enjoyable snack, but in the end I found it easiest to add the powder into my morning shake.

Unfortunately, I can't say I noticed much of the positive effects maca is supposed to have. Granted, my energy level and libido were good during the experiment, but they were good before and still are, even though I have stopped taking it. My approach certainly could have been more scientific as far as sperm count and motility is concerned, but if there was an effect, it wasn't visible to the naked eye.

I also had days where I skipped the maca entirely, just to see whether there would be differences in how I felt between the days I took it and the days I didn't. I didn't notice any. Changing the size of the dosage didn't seem to have much effect either.

These results are a bit disappointing, given that there are studies on maca that seem pretty conclusive. The rat studies I wrote about in my previous post showed increased sperm counts, and in human studies the subjects who took maca reported increases in sexual desire, sperm counts and sperm motility.

One could argue that maca only has an effect in those whose energy level or libido is lacking to begin with, but the studies suggest that it should work on anyone. The double-blind study on humans included healthy, young men as well, and in one of the rat studies the sperm counts of the maca-fed rats exposed to high altitudes were not only higher than the control group's but also higher than the sea-level group's that was not fed maca.

Another thing that is noteworthy is that the amounts used in the studies were very small. The humans were fed either 1,500 mg or 3,000 mg maca. That's even less than a teaspoon, so you'd think two tablespoons would have at least some effect.

One of the studies mentioned that the only type of maca that showed benefits was "red maca". Yellow and black maca had no effect on prostate size. The maca powder I purchased was clearly yellow, which could be one reason I didn't notice much.

In short, I can't completely rule out the possibility that consuming between one teaspoon and two tablespoons of maca affected me, but any effect must have been fairly small. Since there's no evidence of maca being toxic at even high doses, you may want to try it for yourself and see what happens. Or if you already have, drop a comment and let me know how you felt while taking it.

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Thursday, January 8, 2009

End Aging to End Anxiety: Filmmaker Jason Silva Talks about Immortality

Jason's short film "The Immortalist"

Brave New Traveler has an interview with Venezuelan-American filmmaker Jason Silva about how to end aging and live forever. The answer: science.

In the interview, Jason mentions looking for answers in different religions at first, but in the end settling on scientific research. He also drops names like Aubrey de Grey and Ray Kurzweil, who are some of the biggest names in the field of anti-aging.

Kurzweil is also featured in Silva's short film "The Immortals" (posted above), which I warmly recommend watching if dying and aging don't strike you as the finer things in life. And if they do, well, I still recommend watching it!

Here's a quote from the interview:

"I believe humans have always overcome their biological limitations. It is what has brought us out of the caves and onto the moon.

We have cured ourselves of diseases, we fly remarkable machines through the air at 500 miles per hour. We communicate instantly and wirelessly across the world.

Why is it such a stretch to imagine us re-programming our biochemistry (much like computer software) so that we may alleviate suffering, decay, and death?"

Clearly, Silva and I agree that natural does not always equal good. It's precisely our ability to change that which is natural that is the reason humans have evolved and survived for so long. Silva also quotes a line from Ernest Becker's book The Denial of Death to illustrate his point. The quote sums up the problem of the finitiness of life perfectly, though horrifically:

"Man creates illusions under which to live in order to distract himself from the awareness of his mortality, which is unbearable."

I'm glad there are people who dare to attempt to solve the problem of mortality. Maybe then we can get rid of the illusions once and for all.

For more information on anti-aging and longevity, see these posts:

Growing New Body Parts: Breakthroughs in Regenerative Medicine
Drinking 10 Cups of Green Tea Daily and Not Smoking Could Add 12 Years to Your Life
Green Tea Reduces the Formation of AGEs
How the Accumulation of Minerals Might Cause Aging in Humans

Read More......

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Tuesday, January 6, 2009

Playing a Memory Game to Improve Intelligence and Increase Your IQ Score?

Remember the letters and improve your IQ. (Photo by Lainey's Repertoire)

It is widely believed that a person's intelligence is genetically fixed from birth and unchangeable by environment. If you're intelligent, good for you; if you're not the sharpest pencil in the box, tough luck.

This idea has now been put in question by Jaeggi et al. who studied the effects of playing a memory game on IQ scores. It's known that people can increase their IQ scores by taking lots of IQ tests, but all that means is that people get better at taking IQ tests – their intelligence in general does not improve. That is, the learning that happens when taking tests repeateadly is not transferable to other tasks.

Intelligence and working memory

The ability to reason and solve new problems independently of previously acquired knowledge is known as fluid intelligence, which is what IQ tests attempt to measure. And they do measure it quite well, as long as they remain novel to the person taking them. With enough practice, however, the test fails to accurately measure a person's fluid intelligence anymore.

The authors of the study propose that by improving working memory, a person can also increase fluid intelligence. The reason is that working memory and intelligence share a common capacity constraint. Basically, the more things you're able to hold in your working memory, the more interrelationships among elements you can keep in mind in a reasoning task. And the ability to solve reasoning tasks is, of course, what IQ tests measure and what intelligence is thought to be.

The dual n-back game

To prove their point, the authors developed a game that improves working memory and then divided the subjects into two groups. Both groups took two IQ tests; one the first day, and a second one some days later. During these between days, the first group practiced their working memory by playing the game.

Sure enough, the IQ scores of the group that played the game increased significantly more than the control group's. Even the control group scored better the second time around, which proves the point about learning how to take the test better by practicing.

The game itself, called dual n-back, is of that "simple to learn, hard to master" type. You can download it for free here. The letter n in the name refers to the number of items you have to keep in your working memory. The number increases as you perform better.

In the game, you hear a letter every 3 seconds, and you have to match it with previous letters you've heard. For example, if n=2, and you hear the letters "A", "B", "F", "B", you press the letter match button to indicate that the last B matches with the previous B, which you heard 2 letters back (hence, n-back). If n=3, you should not press the button, since "B" does not match with "A". You get a point for every match you catch and lose a point for every incorrect match and missed match.

If this sounds difficult, it gets worse. The dual part of the name comes from the fact that in addition to having to remember the letters, you also have to remember a visual signal that is presented with the letters. Every three seconds, a blue box appears in one of 8 positions on the screen, and again, you have the match them. The letters and boxes don't correlate in any way, meaning that you have to keep both things in mind all the time.

The study

The first few times you try the game, it seems impossible. But as you keep playing, you start getting better at it. Here is a graph depicting how the test subjects did in the game:

The subjects in the game group were further divided into four groups, each with a different number of training days before the second IQ test. As you can see, the number of items they could keep in the working memory increased with each training session in all groups. The 19 day group got all the way up to n>5.

Note that the mean n-back level of all groups is a respectable 3 even after the first day. And these subjects were normal people, not geniuses. Since the amount of games per training session was 20, this means that if you're averagely intelligent, you should be able to play the game with the "dual 3-back" setting after 20 tries.

The inhuman experiment

Who doesn't want to be smarter? At least to me, improving general intelligence just seems too good to pass on, so in the spirit of this blog, I'm going to make an experiment of this.

To match the study as closely as possible, I tested myself on two free IQ tests available on the web before playing the game. I've now played it for a couple of days, and even though it seemed extremely difficult at first, I've gradually gotten better at it. Still, scoring properly even with the 3-back setting still seems quite hard.

After 20 days, I'm going to take the same IQ tests again and see if there's an improvement. If you download the game, drop a comment and let me know how you're doing!

For more information on brains and intelligence, see these posts:

Increasing Intelligence by Playing a Memory Game – Experiment Update
Caloric Restriction Improves Memory in the Elderly
Moderate and Severe Calorie Restriction Alter Behavior Differently in Rats
How the Accumulation of Minerals Might Cause Aging

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Monday, January 5, 2009

Growing New Body Parts: Breakthroughs in Regenerative Medicine

Why not engineer new tissue and organs to replace sick ones?

I came upon this fascinating video on regenerative medicine and thought I'd share it. It was posted on some time ago, but the stuff Alan Russell talks about in his presentation is still very relevant.

If you're not sure where we currently are in terms of growing new body parts and tissue, you might be positively surprised after watching this video. What's interesting is that it's not just about growing organs in a lab somewhere and then transferring them inside patients (even though that's a cool breakthrough too); it's about making the body regrow its own parts. Sound like sci-fi? Fortunately, it's not.

Though some of the "before" images of infected and sick body parts are somewhat grotesque, the "after" images of the results from these new technologies are pretty awe-inspiring.

Watch out especially for the regrown finger.

For more information on anti-aging and longevity, see these posts:

End Aging to End Anxiety: Filmmaker Jason Silva Talks about Immortality
Drinking 10 Cups of Green Tea Daily and Not Smoking Could Add 12 Years to Your Life
Green Tea Reduces the Formation of AGEs
How the Accumulation of Minerals Might Cause Aging in Humans

Read More......

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Sunday, January 4, 2009

Sesame Seeds Increase Absorption of Vitamin E Tocotrienols by Up to 500%

A tablespoon of sesame seeds daily might be enough to do the trick. (Photo by rick)

As you may know, I'm currently taking a tocotrienol supplement called Toco-Sorb to see whether it has an effect on hair growth (if you stumbled upon this post by accident, you can read the beginning of the experiment here).

The challenge

A couple of weeks ago I wrote a post about getting tocotrienols from natural sources. The conlusion was that most foods are so low in tocotrienols that getting the whole tocotrienol complex is difficult, if not impossible, without supplements.

Another problem with tocotrienols is that they're poorly absorbed. The figures I've seen are in the 20-30% range, meaning that at best only a third of the tocotrienols are actually absorbed. So even if you forget the natural way and go for the supplement cabinet to get those tocotrienols, the question of bioavailability still remains.

Then how do we increase the bioavailability of tocotrienols? One answer seems to be sesame seeds.

Feeding rats vitamin E and sesame seeds

In their first experiment, Ikeda et al. fed rats tocopherol with or without tocotrienols. In the second experiment, they fed rats tocopherol or tocotrienols with or without sesame seeds.

As both experiments had control groups as well, the rats in the first experiment were divided into three groups: the first one was fed no vitamin E at all, the second one was fed only alpha-tocopherol, and the third one was fed a palm oil extract with alpha-tocopherol, alpha-tocotrienol and gamma-tocotrienol.

In the second experiment the rats were divided into five groups: the first was fed no vitamin E, the second was fed alpha- and gamma-tocopherol, the third was fed alpha-tocopherol and sesame seeds, the fourth was fed the palm fruit extract and gamma-tocopherol, and the fifth was fed the palm fruit extract with sesame seeds.

Tocotrienols are absorbed only by fat and skin tissues

Since it's the second experiment and its sesame seed groups we're interested in, I'll skip analyzing the first experiment in detail.

The researchers found that, in the second experiment, tocotrienols were not detected in any tissues or plasma in the first three groups (no vitamin E, alpha- and gamma-tocopherol, alpha-tocopherol + sesame seeds). Only negligible levels of tocotrienols were detected in the liver, kidney, heart, lung, brain, muscle and plasma of the last two groups (palm fruit extract + gamma-tocopherol, palm fruit extract + sesame seeds).

However, in the last two groups, tocotrienols were detected in fat and skin tissues. The fifth group also had higher levels than the fourth group.

Sesame seeds improve absorption of tocotrienols

What this means is that consuming the palm oil extract resulted in detectable levels of tocotrienols in fat and skin tissues but not in other tissues. So while the bioavailability of tocotrienols might not be optimal, at least some of them are absorbed by fat and skin tissues in rats.

That's good news of course, but even better news is that when sesame seeds were consumed with the extract, the tocotrienol levels were even higher:

Absorption of tocotrienols
In the graphs above, the bottom row labels refer to alpha-tocopherol, gamma-tocopherol, alpha-tocotrienol and gamma-tocotrienol. The five bars above each label represent the five groups of the second experiment. The numbers are mmol/g.

The black bar is thus group four, i.e. the one fed palm oil extract and gamma-tocopherol, and the rightmost bar is group five, i.e. the one fed the palm oil extract and sesame seeds. As you can see, only the groups fed palm fruit extract had detectable levels of tocotrienols in perirenal adipose tissues, epidymal fat tissues and skin tissues.

The most interesting thing is how strongly sesame seeds increased the tocotrienol levels in these tissues. In fat tissues alpha-tocotrienol levels increased about 50%, and in skin tissues by about 80%. A pretty significant increase. Even more significant is the effect of sesame seeds on gamma-tocotrienol levels: gamma-tocotrienol levels increased in fat tissues by about 400%, and by about 500% in skin tissues.

These are exciting figures – even higher than the "2-3 times better bioavailability" advertised (but unreferenced) by Jarrow on the label of their Toco-Sorb product.

Applying the results to humans

The amount of sesame seeds used in the study was 200 mg per kg of feed. If we assume the male Wistar rats weighed about 400 grams, and that the rats ate daily about 6% of their body weight in solid food (these seem to be common figures in male rats), we get 24 grams of food per day per rat.

The amount of sesame seeds eaten per day is then 0.2 grams * 24 grams = 4.8 grams. This number may not be directly applicable to humans, but it certainly seems that a huge amount of sesame seeds is not needed to see the increased absorption of tocotrienols. In fact, compared to trying to consume more actual tocotrienols by eating more natural foods, this seems like a remarkably easy way.

Since my experiment is mainly about the effect of tocotrienols on hair growth, the fact that sesame seeds improve absorption into skin tissue is the most interesting result of the study. I'm now adding a tablespoon of sesame seeds (about 9 grams) into my morning smoothie and taking my tocotrienol supplement with it.

For more information on tocotrienols, see these posts:

Getting Tocotrienols from Natural Food Sources: Is It Possible?
Hair Growth with Vitamin E Tocotrienols from Palm Oil – Experiment Conclusion
Vitamin E Tocotrienols May Grow Hair in Humans

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Friday, January 2, 2009

Drinking 10 Cups of Green Tea Daily and Not Smoking Could Add 12 Years to Your Life

Drinking green tea and not smoking could add over a decade to your life
Drinking green tea and not smoking could add over a decade to your life. (Photo by Kanko*)

Since green tea has such a wide range of health benefits, it is commonly assumed that drinking green tea slows down aging in general. However, epidemiological proof of tea extending lifespan is lacking for the most part.

Now it seems that this hypothesis has indeed been proven true. Nakachi et al. followed the green tea consumption and deaths (cancer, cardiovascular death and all cause mortality) in a Japanese population for 13 years. Since the Japanese have one of the longest life expectancies in the world, they're ideal for a study like this.

Green tea and cancer

The authors found that onset of cancer and death from cancer were significantly delayed in those who drank the most green tea. That is, they developed cancer later and died from cancer later than those who drank less tea. Compared to people who drank three cups or less per day, those who consumed at least 10 cups had a 41% less chance of getting cancer.

The cancer-preventative effect was more pronounced in women than men: mean age at cancer onset in women who drank more than 10 cups was 7.6 years later than in those who drank less than three cups, whereas in men the delay was 4.1 years. The difference in age at cancer death was 3.9 years and 5.9 years in men and women, respectively.

Cancer deaths and green tea consumption
The figure above shows the age-specific cancer death rates among women by daily consumption of green tea. You can see that up until the age of 80, higher green tea consumption correlates with less cancer rather clearly, but after that the data gets mixed.

Green tea and cardiovascular deaths

Cardiovascular deaths were similarly inversely correlated with green tea consumption in both men and women.

In men, mean age at cardiovascular death was 74.9 years in those who drank up to 3 cups, 76.2 years in those who drank 4-9 cups, and 76.8 years in those who drank more than 10 cups. In women, the values were 79.5 years, 80.6 years, and 80.9 years. Even though the women lived longer, here the effect of green tea on lifespan was more pronounced in men.

Green tea and all cause death

Mean age at death among men and women drinking more than 10 cups per day was 4.3 and 3.8 years higher, respectively, than those consuming less than three cups.

The largest difference in age of death was observed between smokers who drank less than 3 cups and non-smokers who drank more than 10 cups: mean ages of death were 67.7 and 79.4 years, respectively. So drinking lots of green tea and not smoking extended lifespan by more than ten years.

Cumulative survival and green tea consumption
The figure above shows the cumulative survival among women over 40 by daily consumption of green tea. Again, those who drank more had a better chance of surviving onto the next year: 74% of those who drank up to three cups, 80% of those who drank 4-9 cups, and 82% of those who drank more than 10 cups were alive at age 80. After that, the differences became smaller.

The authors conclude:

The median survival time (equivalent to average lifespan of women who have already lived to the age of 40) was 87.1, 88.2 or 89.9 years for groups consuming below 3 cups, 4-9 cups, and over 10 cups a day, respectively, indicating about two years longer lifetime associated with large consumption of green tea.

On the other hand, cumulative survival among men did not show such clear differences by consumption of green tea as were seen in women. This is in part due to the deleterious effect of cigarette smoking, which apparently disturbs the beneficial effects of green tea. In fact, when we divided men by smoking status, the life-table analysis among non-smokers showed [that] current smokers consuming over 10 cups a day showed the highest survival in ages before 70, and there were no substantial differences in cumulative survival in ages after 70 between the group consuming over 10 cups and 4-9 cups a day, although smokers consuming below three cups had a much lower survival.


Green tea increases lifespan by preventing death from age-related illnesses, especially cancer. The cancer-protective effect of green tea is especially pronounced in women, whereas the protection from cardiovascular death seems to be stronger in men.

Mean age at death from all causes was ~4 years higher in those who drank more than 10 cups than those who drank less than three cups per day. The best combination was more than 10 cups of green tea and no smoking, whereas the worst combination was less than three cups of green tea plus smoking. The difference in age of death between these two groups was almost 12 years.

If you're after those extra years, you should start drinking green tea during middle age or earlier. And even though more may not always be better, in this case it seems to be: if you can handle 10 cups per day like some of the Japanese in this study did, go for it.

For more information on green tea, see these posts:

Green Tea, Black Tea & Oolong Tea Increase Insulin Activity by More than 1500%
Green Tea Grows Hair in Vitro, Might Work in Vivo
Green Tea Reduces the Formation of AGEs
Dental Health Effects of Green and Black Tea

Read More......

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