Fat officially not bad for you

HEALTH FOOD? (PHOTO: ULRIK)

Doesn't it seem that every time you read a story about a new study it's the "biggest study of its kind." Or "most exhaustive", "most complete" or something? Well the New York Times has really taken the cake with their write up of a new "Rolls-Royce study" on low fat diets and health implications.

Okay, okay so it's a really big and expensive and important study: researchers found that lowering fat intake had NO EFFECT on risk of breast cancer, colon cancer, heart attack and stroke among 49,000 middle aged women. NO EFFECT, PEOPLE. The low fat craze of the 80s and 90s was ALL IN VAIN.

But let's delve deeper. In point form

• We all know that there are different types of fats, some that actually seem to protect against cancer and heart disease. Like olive oil. So the fact that overall low-fat diets had no protective effect should not be surprising. They cut out the good stuff, too
• What foods were these ladies replacing the tasty tasty fat with? Veggies? Non-fat "butter-like" spray and uber low-fat chemically cheese? Ever look at the ingredients of fat-free cookies, mayonnaise or salad dressing? You don't have to be a biochemist to realise the bad factor.
• Maybe fat isn't bad for us. It's just that becuase fat is the most calorie dense nutrient, it rapidly assists us in growing over-weight...note that low-fat and higher fat ladies tended to consume similar amounts of calories in this study.

There are lots of different view points from lots of different specialists in the NYT article. Some say that this study is like a slap in the face for health scientists - who give out strong advice based on weak evidence. And I agree with that to a certain extent. I am not going to start eating a blueberry-only diet based on a small pilot study showing it to be the formula for immortality. But equally, I don't need a $1.5 billion dollar study following every man woman and child in Utah for 17 years to convince me of a little common sense.....eat more unprocessed foods, quit smoking and exercise. Yes,our understanding of fat and carbohydrate metabolism has changed, but has it really REALLY altered what we know in our bones is "healthy?"

Comments

[The Don Wood Files]

This reversal hurts not only health science. All pronostications can be legitmately doubted now. Is it any wonder that some people, for example, remain unconvinced that global warming is a catastrophe-in-the-making? WHat will the next study show?

Something has to give. Journalists have to get better at what they do - becoming more questioning, actually read the data, etc - and scientists have to point out, up front, the weaknesses of their own data. Right now, that is not happening.

If we can't get it right on diet, how can we get it right on climate, GM foods, nano, and other developing issues that some scientists have made a career out of scaring people about?

[sara]

As a person who tries to put numbers to scientific claims (as well as explain the meaning of the numbers to various biologists), it's a really tough problem.

First of all, people want to make far-reaching claims, like 'fat is bad' and 'vegetables are good', etc. These kinds of hypotheses are almost impossible to test from a scientific standpoint -- there are too many variables such as evironment, genetics, exercise habits, etc.

Second, it's difficult to digest the probabilities and statistics that come from these studies. Even within the field of probability, there is a huge debate between the frequentist view of probability (I believe something will happen 50% of the time) and the bayesian view (I have a 50% belief that something will happen) and the math is all different. So once we get numbers for studies, there is the problem of translating them into something useful.