Food & Nutrition

For those of you who don’t know me that well, I spend a lot of my spare time reading, mostly engineering (audio, speech, DSP type stuff), but also alot of articles/papers on food & nutrition. Unfortunately, my family is sort of plagued with a lot of bad health problems — most of my mom’s side has high blood pressure and heart problems. So, I’m always trying to figure out the best way to maximize my odds of living to a ripe old age.

What’s funny is that most of the stuff I read, that is most of the stuff that is new research and is generally considering to be “correct”, is widely unknown by the mainstream and the media. For example, most people I talk to (including dieticians and nutrionalists) still promote a low-fat diet for weight loss or heart problems. But most researchers would agree that a low-fat diet is not only suboptimal for alot of people, it’s actually very dangerous.

A few years ago, I was having trouble keeping my weight down. I was going to the gym five days a week, eating about 1400 calories a day, and yet I wasn’t losing a pound. This went on for about 4 - 6 months, and finally out of frustration I started doing my own research. Someone told me about Atkins, which at the time went completely against everything I had heard or been raised to believe when it comes to nutrition. A few times during those months I bought all the types of food I would eat on Atkin’s, only to throw them away thinking they must be completely bad for me. Finally I caved in, and gave up carbohydrates around Sept 2003.

In short, the next few months went by pretty quick, but by January 2004, I had lost around 30 lbs, with what seemed like little or no effort compared to the rest of my life (all without going to the gym). Since heart disease runs in my family, I have blood work done every year or so to understand what’s going on under the hood. Surprisingly, the best results I ever had (for both blood pressure and cholesterol) was after that period of time.

Dori, Dustin and I have had many conversations about all this stuff over the years, so I thought I would provide some good quotations and links to some cool articles on how things are slowly changing. This will be a long post, but I hope some people will read it and take notice.

• A big surprise at the NIH meeting was a collection of of epidemiologic studies contradicting the conventional wisdom that extra fat shortens lives. David F. Williamson, Ph.D., an epidemiologist in the division of nutrition of the Centers for Disease Control, Atlanta, said that what “made people sit up and take notice” were 15 studies observing trends among several hundreds of thousands of people, all pointing to the possibility that dieting — not being fat — may increase a person’s relative mortality risk about 1.5 to 2.5 times
• The often reported impressive gains in body fat during recovery from malnutrition may result from enhancement in the efficiency of food utilization and a shift in energy partitioning in favor of fat storage. Children recovering from protein- energy malnutrition were fatter than well nourished children of the same age.
• studies suggest that it is the nature of the fatty acids rather than the amount of fat in the diet which is important
• Some ultra high fat (>>40% fat) diets cause weight gain in research rats. Low fat evangelists fail to note that high carbohydrate diets have proven even more fattening to these research rats
• The incidence of obesity does not necessarily follow the amount of dietary fat. The average U.S. daily fat consumption is 2.52 ounces, with 10% of males obese; the average Australian daily fat consumption is much less at , but 14% are obese
• A Harvard Health letter compared results of 1982 and 1991 surveys of doctors’ lifestyles. Since 1982 the doctors reduced their consumption of red meat, fat, and cholesterol. They increased their dietary fiber and exercised more. Unfortunately, the increased attention to diet and exercise did not produce leaner bodies; the proportion reporting weight problems increased from 29 to 39 per cent

These quotes are from an article called Adiposity 101. It’s definitely worth reading.

Another great article I read years ago is by Gary Taubes from the New York times. The article is called What if it’s all been a big fat lie. Here are some of the highlights:

• [the] low-fat weight-loss diets have proved in clinical trials and real life to be dismal failures, and that on top of it all, the percentage of fat in the American diet has been decreasing for two decades. Our cholesterol levels have been declining, and we have been smoking less, and yet the incidence of heart disease has not declined as would be expected. ”That is very disconcerting,” Willett says. ”It suggests that something else bad is happening.”
• In the intervening years, the N.I.H. spent several hundred million dollars trying to demonstrate a connection between eating fat and getting heart disease and, despite what we might think, it failed. Five major studies revealed no such link. A sixth, however, costing well over $100 million alone, concluded that reducing cholesterol by drug therapy could prevent heart disease. The N.I.H. administrators then made a leap of faith.
• when the American Medical Association released its scathing critique of Atkins’s diet in March 1973, it acknowledged that the diet probably worked, but expressed little interest in why

I should point out I’m not a big Atkin’s promoter, although low-carb dieting worked for me years ago. However, I think it’s interesting that many big weights are trying to change the whole fat-is-bad mentality, including Harvard (who has their own food pyramid that places refined carbohydrates near the bottom).

What’s interesting is that the link that ties most of this together is something called hyperinsulinemia. Everyone knows about insulin: it’s the hormone that diabetic individuals are forced to inject because their bodies no longer process enough of it. Insulin causes glucose (sugar) to be transported from the blood into cells throughout the body. For people who are hyperinsulinemic, the body is resistant to the effect of insulin. Because of this, the body is forced to create alot more insulin to do the same job (that is, when eating the same food, the pancreas releases a lot more insulin in a hyperinsulinemic person). Therefore hyperinsulinemia and insulin resistance go hand in hand. The problem is that insulin promotes fat storage, and makes weight loss difficult. To lose weight, insulin levels in the blood must go down to the point where the body release glucagon (they negate each other). Glucagon promotes the breakdown of fat for energy. In hyperinsulinemic individuals, since the body releases so much insulin, it becomes very difficult to lose weight (since no glucagon is in the blood to assist with the breakdown of fat), but very easy to gain weight (since insulin is promoting fat storage). Eventually the amount of insulin required to remove glucose from the blood goes beyond what the body can create. This results in type II diabetes (which used to be called adult-onset diabetes, but can’t be called that anymore since many kids are developing it now).

Hyperinsulinemia is part of a deadly cluster of symptoms known universally as “Syndrome X.” This cluster includes insulin resistance, high blood pressure, high LDL (bad) cholesterol, low HDL (good) cholesterol, admoninal obesity, and high triglycerides (very bad).

I’ll write a big blog entry in a few days on Syndrome X, since I find it very interesting. For now I have to get back to working on my thesis slides.