Food supplements: a big debate

The December 2013 issue of Annals of Internal Medicine published an editorial titled “Enough Is Enough: Stop Wasting Money on Vitamin and Mineral Supplements.” The authors were from Johns Hopkins University and other august institutions. The researchers performed a thorough investigation of  clinical trials that tested the usefulness of supplements. Their conclusion: “We believe that the case is closed— supplementing the diet of well-nourished adults with (most) mineral or vitamin supplements has no clear benefit and might even be harmful.”

On the whole, I agree with this conclusion. If you’re a normal well-fed person, you don’t need supplements. I don’t take any myself. But I have. When I started getting arthritis in my thumb, I tried glucosamine-chondroitin. I did it because a friend of mine had given it to her dogs and they stopped limping! Anyhow, I tried it for many months and noticed no difference. I have since learned that a randomized trial of more than 1,500 people showed no improvement through using this supplement.  I also tried fish oil supplements, but later found out that studies have definitively proved that it has no value. Ditto for calcium and vitamin D: they don’t reduce the risk of fractures. And so on.

But there’s still plenty of debate about this among researchers. Various studies show that some people may be deficient in certain vitamins or minerals. On the other hand, scientists also say we don’t really know the threshold for deficiency. Plus the vast genetic variation among people affects an individual’s requirements for vitamins and minerals. It’s all very complicated.

Here’s my favorite story about mineral deficiency: A man suddenly found that everything smelled and tasted either rotten or very strong. “All I could do was stand in the woods all day.” He could eat only a few things, mostly cold and white. He went to doctor after doctor until finally one figured out his problem: his saliva had no zinc in it. He was cured with a prescription for zinc sulfate. This condition, by the way, is usually triggered by a bout of flu or a stay in the hospital. Go figure.

While I don’t take any supplements, in the past I have found that a mineral supplement containing calcium, magnesium, potassium, etc. prevented muscle cramps, which, for some reason, I don’t get anymore. But my husband and friend Susan take two a day. It has reduced my husband’s cramps considerably; it has eliminated Susan’s cramps entirely. It’s called Skeletal Strength from Nature’s Sunshine.

Next week: Cartoons for the holidays (I)

For an introduction to this blog, see I Just Say No; for a list of blog topics, click the Topics tab.

In defense of fat people

In researching and writing my book, Fat—It’s Not What You Think, I became even more sympathetic towards fat people than I already was. Sadly, I appear to be in the minority. Most people—even those I consider friends—think that people are fat because they don’t exercise or eat properly. As The Scientist Magazine reports, “This antiquated view of the cause of obesity is still widespread, even among medical professionals.” According to scientific research, “poor lifestyle choices” account for only about 15 pounds of weight gain.

Look at yourself and those about you: as the years go by your weight stays about the same. I have fat friends and thin friends. We all exercise and eat sensibly. My fat friends stay fat; my thin friends stay thin (and I remain somewhere in between). The system that regulates our weight is a highly complex one that keeps our weight within a narrow range. Our fat cells maintain equilibrium between the forces that deposit fat and the forces that release fat. The filling and emptying is regulated by feedback systems, chiefly the nervous system and the endocrine (hormone) system. Neither eating less nor exercising more will lead to long-term weight loss because our bodies naturally compensate.

For most obese people, an equally complex system is at work to maintain an overweight condition. Scientists have been studying this for years. For example, researchers hospitalized a 348-pound woman to study the relationship between her food intake and her obesity. For weeks, they fed her exactly the number of calories they calculated would keep her weight at 348. Instead, she gained twelve pounds in two weeks.

Generally speaking, lean people are more active than fat people because a greater proportion of the food they consume is made available to their cells and tissues for energy. With energy to burn, they’re more inclined to be restless and impelled to be physically active. The opposite is true of obese people: the calories they consume go to making fat rather than to burn for energy.

Like much else, having a body that tends toward obesity is simply bad luck. As for the rise in obesity world-wide, Dr. Rudy Liebel, a long-time obesity researcher and fellow sympathizer says, “We simply do not know what environment factors account for the increased prevalence of obesity.”

Next week: Food supplements: a big debate

For an introduction to this blog, see I Just Say No; for a list of blog topics, click the Topics tab.

A dose of radiation for health?

Sixteen hundred people died following the Fukushima nuclear accident. But scientists have recently found that none of the deaths were caused by radiation. “It was the fear of radiation that ended up killing people” says Dr. Mohan Doss, a medical physicist. “The government basically panicked.” Many of those who died were evacuated from intensive care units and other health facilities and did not survive the move. Some deaths were suicides.

If people had stayed put, they would have been OK. Even in the hottest spots, their exposure would have been roughly comparable to receiving a high-resolution whole-body scan each year. But most residents would have received far less radiation. Below a certain threshold, according to Dr. Doss and other scientists, low doses are harmless and possibly even beneficial. The phenomenon of beneficial radiation is called radiation hormesis, which means that weak radiation can have favorable effects. Life evolved in a mildly radioactive environment. What’s more we’re all exposed to a natural “background radiation” from the earth (an amount less than half of what most Fukushima residents received).

Some laboratory experiments and animal studies have shown that low exposures unleash protective antioxidants and stimulate our immune systems, conceivably protecting against cancers. Thirty years ago in Taiwan, authorities discovered that about 200 buildings housing 10,000 people were constructed from steel contaminated with radioactive cobalt. Over the years residents were exposed to double the average for the people of Fukushima. Yet a study in 2006 found fewer cancer cases among these folks compared with the general public. More recently, a study of radon by Johns Hopkins scientist suggested that people living with higher concentrations of the radioactive gas had correspondingly lower rates of lung cancer.

I like the idea of hormesis—the notion that low exposure to toxins and other stressors can be good for you. While scientists don’t know the exact biochemical mechanisms by which it works, the general belief is that low doses of otherwise toxic substances can stimulate our bodies’ natural repair mechanisms. I like the theory because it fits with my overall approach to health: don’t worry about it.

Next week: In defense of fat people

For an introduction to this blog, see I Just Say No; for a list of blog topics, click the Topics tab.

Sleep update: some new information

I have written several posts about sleep (see the Topics menu for a list), the gist of which is not to worry if you don’t get eight hours of uninterrupted sleep. New research, published in Current Biology, underscores that message and adds new information.

Researchers studied the sleep habits of three hunter-gatherer societies, two in Africa (The Hadza and San tribes) and one in Bolivia (the Tismane people). These tribes live much as their ancestors have for tens of thousands of years. By studying these people, the researchers could determine how early humans were “programmed” to sleep, and, by extension, what normal sleep might be for us. (Of course, manufacturers of Ambien and Lunesta would have you believe that less than eight hours of sleep will have dire consequences.) Like early humans, the hunter-gatherer people sleep outside or in crude huts and their only light at night comes from fire.

What the researchers found is that, on a typical night, these people sleep slightly less than the average American. In the US, most adults sleep seven hours or more a night--although many sleep significantly less. Members of these hunter-gatherer tribes slept just six and a half hours. About like me. Researchers also found that the presence or absence of daylight is not the primary factor in their sleep patterns.

The conventional thinking has been that the artificial light throws off our biological clocks and that if we could live like early humans, going to bed when the sun goes down and getting up when the sun comes up, we’d be much better off. It turns out that the people in all three of these tribes do not follow that sundown/sunup scenario. Instead, they stay awake several hours after the sun goes down and do not wake at sunrise. What does determine their sleep habits is temperature. They almost always fall asleep as the temperature begins to fall at night and wake up as the temperature rises in the morning. This habit suggests that humans may have evolved to sleep during the coldest hours of the day, perhaps as a way to conserve energy.

From what I can observe, most of us modern humans like sleeping in a cool bedroom. In the 20 years we have lived in our house, we have never turned the heat on in our bedroom (it has its own heat zone). We also open windows at night. Most people I know do the same thing. We seem to have figured it out ourselves.

Next week: A dose of radiation for health?

For an introduction to this blog, see I Just Say No; for a list of blog topics, click the Topics tab.