Does Atkins make sense?
I have long doubted that cutting carbs is the key to losing weight, as proponents of the Atkins diet claim. But recent evidence has forced me to reconsider. I’m still not convinced that the Atkins approach is more effective or more healthful than others, but I now believe it can help overweight people shed pounds.
What changed my mind was a spate of new studies comparing the Atkins diet with low-fat or low-calorie regimens. In the first study, involving 79 overweight people, those on Atkins lost 13 pounds over six months, while those on the American Heart Association diet lost only four. In the second study, obese women shed 15.4 pounds by counting carbs for six months but only seven by counting calories and fat. The third study compared Atkins with three other popular diets (Ornish, Weight Watchers and the Zone), and found that all four brought significant weight loss over a year’s time. Atkins worked no better than the other diets–but it worked.
These studies tell us nothing about long-term weight management. We know only that Atkins can work as a short-term strategy. But the findings support a central tenet of the low-carb faith: that a relatively fatty diet may help you lose weight because it makes food more satisfying and filling.
I agree that the Atkins diet can produce short-term weight loss, but a diet should promote long-term weight loss and better overall health. A high-fat regimen is unlikely to help you achieve either of those goals.
Suppose you went on an 800-calorie per day diet, in which all 800 calories were in the form of hot-fudge sundaes. You would lose weight on that diet, but would it be healthy? The original Atkins diet was not that different from a hot-fudge sundae diet. It sanctioned steak, bacon, cheese and butter, while banning not only sweets but also bread, pasta, grains, many fruits and some starchy vegetables. This advice flies in the face of overwhelming evidence that diets high in fruits, vegetables and whole grains are healthy.
The latest version of the Atkins diet is more sensible. Even some healthy (whole- grain) carbohydrates are allowed, though in moderation. But it still goes wrong in sanctioning unlimited saturated fat. Unless larger studies show that it helps people keep weight off for a long time, and that this weight loss brings the expected health benefits, then studies showing short-term weight loss just don’t mean very much. If you’re determined to try the Atkins diet, swap the steak and bacon for fish or chicken with a fresh vegetable sauteed in olive oil. And add some fruit and some whole-grain, high-fiber foods. That’s a healthier low-carb diet.
Should we expand the use of statin drugs?
It has been clear for several years that most people with heart disease or very high cholesterol levels should take statin drugs. It’s now clear that other people can benefit, too. I now favor prescribing them to anyone at high risk of cardiovascular disease–even if her cholesterol levels are normal. This is a de–parture from government guidelines, but it’s well supported by recent studies. Those studies suggest that almost anyone with high blood pressure or type 2 diabetes is a good candidate for statins.
Determining whether to prescribe a drug requires balancing benefits against hazards. We know statins prevent heart attacks and only rarely cause significant side effects. The greater a person’s risk of heart disease or stroke, the greater the likely benefit. So instead of looking only at cholesterol, I use a global assessment of risk to gauge the need for treatment.
If a person has more than a 20 percent chance of suffering a heart attack or dying of cardiovascular disease within 10 years, I generally prescribe statins. If the risk ranges from 10 to 20 percent, I discuss the pros and cons of statins, and prescribe treatment for patients who decide it makes sense. In people whose risk is below 10 percent, I generally do not prescribe statins.
You can assess your own 10-year risk by going to health.harvard.edu/heartrisk.
I agree that the evidence now supports prescribing statins to a larger number of people, but I don’t believe that everyone with any risk factor for heart disease should take a statin–and the guidelines from the American College of Cardiology and American Heart Association are on my side.
Statins have an extraordinarily good safety record, but every pill has potential side effects. Good studies have suggested that statins are beneficial for people with hypertension or diabetes. But we don’t yet have enough evidence to justify treating everyone with those conditions. I also worry about our tendency to try to fix every problem with a pill. People with hypertension, diabetes or high cholesterol should be exercising and trying to lose weight. That hard work will lower several risk factors for heart disease and other conditions. Statins may lull them into thinking that lifestyle choices don’t matter.
To see whether you qualify for statins under the 2001 guidelines of the National Cholesterol Education Program, go to health.harvard.edu/cholesterol.
Are plain old diuretics best for blood pressure?
You won’t see TV or magazine ads promoting older blood-pressure-lowering drugs, and you won’t find many free samples in doctors’ offices. Their patents have expired, which means that they don’t generate large profits for pharmaceutical companies. Yet these time-tested treatments–the diuretics and beta blockers–are still the best weapons we have against hypertension. Before turning to costly new treatments, doctors and patients should give them a try.
Until recently, no one knew which blood- pressure drugs worked best. Today there is little question. In late 2002, a huge study known as ALLHAT found that a diuretic (chlorthalidone), a calcium channel blocker (amlodipine) and an angiotensin-converting-enzyme (ACE) inhibitor (lisinopril) all had similar effects on heart-attack risk and overall mortality. In fact, the chlorthalidone patients suffered less heart failure, stroke and angina than those receiving the newer, costlier drugs. The authors of the study concluded that the diuretics “should be considered first” when people need blood-pressure drugs. I agree, and so does the panel that writes the government’s treatment guidelines.
All these drugs are effective for lowering blood pressure, and all of them cause side effects. But patients have unique needs. Instead of simply starting everyone on the same medication, we can now tailor the treatment to the individual. I think every patient deserves the best possible fit.
I don’t question the value of diuretics. Besides being effective, they are convenient (one pill a day), inexpensive and particularly effective for African-Americans. I use them for many patients. But if a patient suffers from congestive heart failure, diabetes or some kidney diseases, I start with an ACE inhibitor. ALLHAT aside, many large studies have shown that ACE inhibitors (and related drugs called angiotensin receptor blockers, or ARBs) are superior weapons for preventing and treating heart failure. Likewise, the calcium channel blockers may be particularly useful when patients with high blood pressure also have angina or migraine headaches.
Doctors may still disagree on the best drug to give a patient with newly diagnosed high blood pressure. The good news is that we have a range of excellent options. For more information about high blood pressure from Harvard Medical School, visit health.harvard.edu/hbp.
