Foods get their calories from protein, fats and carbohydrates. Most of the calories you eat come from carbohydrates and fats. Carbohydrates are starches and sugars, which are in foods like bread, pasta and sweets. Low-carbohydrate diets (or low-carb diets, for short) cut down on the amount of calories you get from sugars and starches.
People on low-carb diets eat less bread, pasta, potatoes, rice and cereals. They usually eat more vegetables, meat, fish, cheese, eggs and nuts.
Whenever people eat fewer calories than their bodies use, they lose weight. People on a low-carb diet usually take in fewer calories, even though they are eating more protein and fats than usual. Low-carb diets have been shown to help people who are overweight lose weight. These diets may work better than low-fat diets when people first start dieting.
After the first six months, though, low-carb diets do not work any better than other diets.
Not enough research has been done to determine whether low-carb diets are safe. Low-carb diets usually do not raise cholesterol levels in most people. In fact, they may improve your cholesterol level if you lose weight. However, some people on these diets may experience short-term side effects such as constipation, diarrhea, dizziness, bad breath, headaches, sleeping problems or nausea.
If you have had a stroke or if you have diabetes, heart disease, high cholesterol levels, kidney stones or if you are pregnant, talk to your doctor before starting a low-carb diet.
Yes. People on low-carb diets may not get enough vitamins, minerals and fiber. Many of these nutrients are found in carbohydrate-rich foods such as fruits and whole grains. If you are on a low-carb diet, you should take a multivitamin and a fiber supplement (one brand: Metamucil) every day.
Written by familydoctor.org editorial staff