Low-Carb Diets: Good or Bad for Your Health?
Not a week goes by without another diet appearing in the news, accompanied by hundreds of personal testimonials from people claiming to have lost massive amounts of weight effortlessly. Low-carbohydrate diets have been going in and out of fashion ever since the work of Dr. Stillman in 1967 and Dr. Atkins in 1972. Although they are effective for short-term weight loss, they are not recommended for periods of longer than a few weeks.
The Physics of Dieting
The basic science behind all forms of dieting is the concept of caloric balance. If you burn more calories than you consume, you lose weight. If you eat more calories than you expend, you gain weight. Since one pound is the equivalent of 3,500 calories, in order to lose one pound in a week, you need to consume 500 fewer calories per day than you expend, either by eating less or exercising more.
Not All Weight Is Fat
When dieters say they want to lose weight, what they mean is that they want to lose fat. If you take a bikram yoga class or sit in a sauna, the weight you lose is water, not fat, and you regain it the instant you have a drink. Even worse, dehydration can damage your liver and kidneys. Very low-calorie diets can also cause you to lose muscle, reducing your metabolic rate and making your body flabby rather than toned.
Effectiveness of Low-Carbohydrate Diets
Low-carbohydrate diets are effective for a few reasons. First, because fat and protein can make you feel fuller than carbohydrates, you may actually consume fewer calories on a low-carbohydrate diet. Second, because of metabolic changes associated with the diet, you will retain slightly less water, causing short-term weight loss. Third, if you make changes to your eating habits to eliminate snacks and junk food, you will lose weight no matter whether you are on a low-carbohydrate or low-fat diet.
Safety
The short-term side effects of low-carbohydrate diets may include nausea, headache, mental and physical fatigue, constipation, and bad breath. Over the long term, you will be missing many essential nutrients, and possible side effects may include osteoporosis, high cholesterol, and kidney disease.
Bottom Line:
If you need to fit into an interview suit or a party dress in one or two weeks, a low-carbohydrate diet is a safe and effective way to drop a few pounds quickly. Over the long term, many low-carbohydrate diets lack essential nutrients and can contain excessive amounts of unhealthy fats. A regular exercise program and balanced diet, including lean proteins, fresh fruits and vegetables, and whole grains is a more effective for long-term weight control.
References:
Centers for Disease Control and Prevention: Healthy Weight — it's not a diet, it's a lifestyle!
National Health Service: Dehydration — Symptoms