High-protein diets: Are they safe?

For most healthy people, a high-protein diet generally isn't harmful if followed for a short time, such as three to four months, and may help with weight loss. However, the risks of using a high-protein diet — usually with carbohydrate restriction — for the long term are still being studied. Several health problems may result if a high-protein diet is followed for an extended time:

• Some high-protein diets restrict carbohydrate intake so much that they can result in nutritional deficiencies or insufficient fiber, which can cause such health problems as constipation and diverticulitis, and may increase your risk for certain types of cancer.
• High-protein diets often promote foods such as red meat and full-fat dairy products. Some experts believe a diet rich in these foods can increase your risk of heart disease.
• A high-protein diet may cause or worsen liver or kidney problems because your body may already have trouble eliminating all the waste products of protein metabolism.

If you want to follow a high-protein diet, do so only as a short-term weight-loss aid. Also, choose your protein wisely. Good choices include fish, skinless chicken, lean beef, pork and low-fat dairy products. Choose carbs that are high in fiber, such as whole grains and nutrient-dense vegetables and fruit. And if you have kidney disease, liver disease or diabetes, if you're taking medication for a chronic health condition, or if you're pregnant or breastfeeding, talk to your doctor before starting a high-protein diet.