Expert Q&A

Low-carb vs. low-fat: Which diet is better for weight loss?

What’s better for weight loss: Low-fat or low-carb? -Cheryl from Colorado

Even the experts argue this question, so it’s understandable that you would wonder which diet to follow. It really depends on your goals and your general health.

Low carb diets

Low carbohydrate diets, like Atkins and South Beach, typically allow more protein and fat. They lead to more short term weight loss than other diets. However, after a year, people on these diets have similar results to other dieters on different types of diets. And they regain weight at a similar rate.

One might assume that high-fat, low-carbohydrate diets increase cholesterol levels. However, this isn’t necessarily true. Nonetheless, these diets are not promoted by physicians because there may be other long-term effects that are less measurable.

Low-fat diets

Low-fat diets include large amounts of low glycemic index vegetables and fruits. Low glycemic foods do not raise blood sugar as quickly as others. This type of diet also enables people to eat more food, which means they’re less hungry most of the time.

Best weight loss: reduced calories (through healthy diet) plus exercise

Essentially, the key to losing weight is reducing calorie intake. No matter what you eat, if you cut calories consistently, you will shed pounds. The important question is: Can you—or should you—sustain the diet you are on forever? If you have risk factors for heart disease, you probably should not eat a high-fat diet for very long. If you stick to a very low-fat diet, you may find it very difficult to eat out or at other peoples’ homes since many foods will not be on your diet. How long do you think you can avoid pizza, ice cream, chips and so on?

If you have to lose 10 pounds fast due to an obesity related disease and your doctor approves, you can lose it quickly on an Atkins type diet. But for long term success, the best diet is a balanced one that you can follow for life. Reduce total calories, use fats sparingly and include many types and colors of vegetables and fruits in small quantities throughout the week. Limit treats to a small amount rarely. And remember that the more calories you burn through exercise, the easier it will be to manage your weight.

John Messmer, MD
Contributing Expert

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