The Effects of a High-Fat Diet on Health and Weight : Does It Raise Blood Pressure?

This is not how you attach a health file to an e-mail. (Photo by Supercapacity)

The unthinkable has happened: the results finally came this morning. I lost hope when I tried to call them last week and ask if they could send them to me by e-mail, and the nurse (who obviously had no clue how to attach a file to an e-mail) got very upset and actually hung up on me. That's customer service right there.

So, now I've got a page full of numbers to interpret. Let's start with blood pressure. According to conventional wisdom, ideal blood pressure values are less than 120/80 mmHg (120 systolic, 80 diastolic). A blood pressure of 140/90 mmHg is considered high blood pressure, while a blood pressure somewhere in between means prehypertension. Then again, in the UK the normal range is 110-140 mmHg for systolic pressure and 70-90 mmHg for diastolic pressure.

My blood pressure is 122/69 mmHg, which is a little difficult to interpret, since the systolic pressure is a little higher than the ideal value and the diastolic pressure is clearly in the ideal range. I don't have a reference value from earlier, so it's hard to say what kind of effect my high-fat diet has had, but I do remember that I've had very low blood pressure for as long as I can remember. Some doctors have even said it was too low. For example, before the diet, I often felt dizzy getting up from bed, which is a sign of low blood pressure.

So, in the light of the evidence, I would have to agree with the conventional wisdom that saturated fat increases blood pressure, at least in individuals (okay, one individual) with very low blood pressure. Whether it increases or lowers blood pressure in people with hypertension is hard to say. Then again, some of the recommended diets for lowering blood pressure, such as the DASH diet, have received criticism for advocating a high intake of carbohydrates.

If you look at the DASH diet plan, you'll see that it's the same diet being advocated by doctors and health professionals all over the western world: lots of grains and grain products (bread, cereals and pasta), low-fat or non-fat dairy foods and small amounts of lean meat and fish. This diet has been the Holy Grail of nutrition for the past few decades, but as you may have noticed by now, I'm very sceptical towards it. The reasons that we are told to eat lots of grains are economical, not biological - bread is full of energy and dirt cheap to produce. That doesn't mean it's healthy for you, however.

Whether my current blood pressure is better or worse than it was before is difficult to say. I haven't really read the studies done in this area, but if you're eating or planning on eating a diet high in saturated fat, be aware that it may raise your (systolic) blood pressure somewhat.

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