The epidemic of obesity has grown dramatically in recent years, most notably in children, one-third of whom have been swept up by weight problems and are at risk for heart disease, diabetes, and certain forms of cancer, among other problems. Unfortunately, the battle against obesity is getting a lot harder. First of all, people trying to lose weight have been lied to. They have been told that the problem is a lack of exercise, when, in fact, studies clearly show that weight gain in the United States over the past 30 years is almost entirely due to changing eating habits, not a lack of physical activity. They have been lied to about food, with quick-fix, low-carb advocates pointing a finger of blame at bread and fruit, when carbohydrates actually have only four calories per gram, unlike fats, which have nine. That’s why people in Asian countries stayed thin and healthy until Western fast-food chains brought in meat, cheese, and other junk foods that displaced traditional rice-based meals. They have been lied to by some well-meaning, but not-yet-well-informed fat-acceptance advocates who, while helpfully rallying against discrimination, have also sought to minimize obesity’s dangers with phrases like “obese but healthy.” You can also be “a smoker, but healthy,” but that simply means the complications have not yet arrived. But most of all, they have been lied to by the meat and dairy industries, which aim to convince us that we need cheese, meat, and other unhealthful foods. The federal government, traditionally beholden to industry, has joined in the duplicity, not only by subsidizing the very foods that cause weight gain and by dumping them into our children’s school lunch programs, but by issuing dietary guidelines that have been too timid to chuck unhealthful foods out. As a result of this lack of forthrightness, obesity has settled in for the long term, and many people have simply become resigned to it for themselves and their children. The consequences will be devastating: Experts estimate that one in three children born in 2000 will go on to develop diabetes—a disease strongly linked to excess weight. The obesity epidemic is not caused by inactivity, bread, rice, gluttony, weak will, or a bad childhood. It is caused by a tsunami of unhealthful foods, and one of the worst, perhaps surprisingly, is cheese. Typical cheeses are about 70 percent fat, and every last fat gram packs nine calories that no one needs. Most of that fat is saturated (“bad”) fat—the kind that increases cholesterol levels and puts us at risk for diabetes, Alzheimer’s disease, and other diseases. A 2-ounce cheese serving also packs 350 milligrams of sodium and, ounce for ounce, as much cholesterol as a heart-stopping steak. In 1909, the average American consumed only 3.8 pounds of cheese in a year’s time. Today, that number is pushing 34 pounds. That’s an increase of 30 pounds per person this year, next year, and again the year after that, thanks to the combined promotional efforts of government and industry. Of those extra 30 pounds of cheese we are stuffing into our mouths every year, it would only take one or two to stick in order to explain the entire weight problem in America. Of course, there are other co-conspirators in the obesity epidemic, too, notably the rise in meat and sugar consumption.
A Wake-Up Call
PCRM erected billboards in New York State depicting a heavy-set man and woman and pointing out, clearly and simply, that cheese contributes to obesity. Judging by the press response, it was a message that was badly needed. Many reporters had no idea that cheese was so high in fat and calories. We knew that the dairy industry would object. But the fact is, dairy farmers and their families need this message, too. After all, they run the same risks as their customers. Some overweight people may object, too. Just as cancer organizations have used images of tobacco-damaged lungs and anti-drunk-driving organizations have shown grim accident scenes, graphic visual reminders are painful for the victims of these conditions. Certainly, there is no value in blaming overweight people for a condition that results from a mixture of industry marketing, government promotions, addictive qualities of foods, genetic vulnerabilities, medication effects on appetite, and, in the end, overeating. Instead, it is essential to zero in on the problem foods, expose them, and do what we can to get them off our collective plates. The PCRM billboards are a mirror, showing obesity as it really is, linking it appropriately to cheese, and making it clear that there is a problem here. The worst thing that doctors or the public can do is to slow down the fight against obesity and against the foods that contribute to it. Prying a generation away from tobacco was tough, and prying people away from obesogenic foods today will be far more challenging. People struggling with weight problems deserve understanding and support, and we do them no favors if we hide the problem, sugar-coat it, or fail to address its causes. We have to face the dangers of obesity directly, make it clear that certain foods are serious problems, and do all we can to support the changes that are essential for good health.
A new study will make people think twice about taking fish-oil capsules—or eating fish, for that matter. The American Journal of Epidemiology reports that men with higher levels of DHA, one of the omega-3 fatty acids found in fish oil, were at increased risk of developing prostate cancer. Researchers from Seattle’s Fred Hutchinson Cancer Research Center looked at 3,461 participants in the Prostate Cancer Prevention Trial and found that men with the most DHA in their bloodstreams were two-and-a-half times more likely to have an aggressive form of prostate cancer. Similar results were found in the European Prospective Investigation into Cancer and Nutrition study, where men who had the highest omega-3 levels had the highest risk for prostate cancer. In many recent studies, fish oil has not lived up to its marketing claims. Specifically, it is no help for heart patients, does not forestall Alzheimer’s disease, does not prevent depression, and—so far at least—does not make babies smarter. Back in 2005, a Journal of the American Medical Association report showed that fish oil may actually increase the risk of cardiac arrhythmia in some patients. In the same year, JAMA also reported that fish oil does not prevent cancer. The following year, the British Medical Journal reported that omega-3 fatty acids have no heart-health benefit. Among nearly 4,000 heart attack patients, no difference was seen between those who consumed omega-3 supplements and those who took placebo pills. That conclusion was echoed in 2009, when researchers found that consuming fish does not reduce the risk of heart failure. Then in 2010, the New England Journal of Medicine reported similarly dismal results with heart patients given omega-3 fatty acids in addition to standard drug therapy. They had no reduction in cardiovascular events. Surprisingly, Harvard linked fish and omega-3 fats to type 2 diabetes. Following 195,204 adults for 14 to 18 years, researchers reported in 2009 that they had found that the more fish or long-chain omega-3 fatty acids participants consumed, the higher their risk of developing diabetes. Meanwhile, fish oil manufacturers pinned their hopes on brain function. Maybe fish oil will make you smarter, they reasoned. But last year, what researchers found dashed those hopes, too. A group of 867 elderly people were randomly assigned to either a fish-oil supplement or placebo. After two years of supplementation, elderly adults showed no benefit at all in tests for reaction time, spatial memory, and processing speed measurements. A later JAMA report showed that omega-3 supplements do not slow mental decline in Alzheimer’s patients. And at the other end of the age spectrum, babies get no benefit either. A JAMA report showed that consumption of fish oil during pregnancy does not benefit babies’ cognitive development. In these reports, fish oil is starting to look a lot like snake oil. The new findings linking higher DHA levels to cancer add yet another reason to skip fish and fish oil supplements. Are you a health professional? Learn more about diet and cancer for continuing education credits at NutritionCME.org. In case you’re interested in the references for these studies, here they are:
Brasky TM, Till C, White E, et al. Serum phospholipid fatty acids and prostate cancer risk: results from the Prostate Cancer Prevention Trial. Am J Epidemiol. Published ahead of print April 24, 2011. doi: 10.1093/aje/kwr027.
Raitt MH, Connor WE, Morris C, et al. Fish oil supplementation and risk of ventricular tachycardia and ventricular fibrillation in patients with implantable defibrillators: a randomized controlled trial. JAMA. 2005;293:2884-2891.
MacLean CH, Newberry SJ, Mojica WA, et al. Effects of omega-3 fatty acids on cancer risk: a systematic review. JAMA. 2005;295:403-415.
Hooper L, Thompson RL, Harrison RA, et al. Risks and benefits of omega-3 fats for mortality, cardiovascular disease, and cancer: systematic review. BMJ. 2006;332:752-760.
Dijkstra SC, Brouwer IA, van Rooij FJA, Hofman A, Witteman JCM, Geleijnse JM. Intake of very long chain n-3 fatty acids from fish and the incidence of heart failure: the Rotterdam Study. Eur J Heart Fail. 2009;11:922-928.
Kromhout D, Giltay EJ, Geleijnse JM. n-3 fatty acids and cardiovascular events after myocardial infarction. N Engl J Med. 2010;363:2015-2026.
Kaushik M, Mozaffarian D, Spiegelman D, Manson JE, Willett WC, Hu FB. Long-chain omega-3 fatty acids, fish intake, and the risk of type 2 diabetes mellitus. Am J Clin Nutr. 2009;90:613-620.
Dangour AD, Allen E, Elbourne D, et al. Effect of 2-y n23 long-chain polyunsaturated fatty acid supplementation on cognitive function in older people: a randomized, double-blind, controlled trial. Am J Clin Nutr. 2010;91:1725-1732.
Quinn JF, Rama R, Thomas RG, et al. Docosahexaenoic acid supplementation and cognitive decline in Alzheimer disease. JAMA. 2010;304:1903-1911.
Makrides M, Gibson RA, McPhee AJ, et al. Effect of DHA Supplementation During Pregnancy on Maternal Depression and Neurodevelopment of Young Children. JAMA. 2010;304:1675-1683.