Your body uses protein to repair cells and produce new ones. How much protein you can safely eat depends on your health, age, gender and activity level. The popularity of high-protein diets raises some concerns about the safety of eating large quantities of protein -- especially animal proteins. Meat tends to be high in saturated fat and dietary cholesterol, which may increase your risk of heart disease.
Your Protein Needs
Protein needs vary, but the U.S. Recommended Daily Allowance for adult women is 46 g of protein daily; men need 56 g of protein each day. Every gram of protein contains 4 calories, so between 10 and 15 percent of your calories should come from protein. Harvard School of Public Health recommends a slightly higher protein intake, based on body weight, of 0.8 g of protein for every kg of body weight -- which works out to roughly 8 g of protein for every 20 lbs. of body weight. A 180-lb. man may need up up to 90 g of protein, rather than 56 g.
High Protein Diets
Many high protein diets, such as the Atkins or Protein Power diets, can require 35 percent of your calories to come from protein, according to Johns Hopkins Medicine. The Zone Diet and Sugar Busters have protein requirements around 30 percent. Harvard notes that healthy individuals can safely consume up to 25 percent of their calories from protein, but that high-protein diets may not be appropriate for people with diabetes or kidney disease. The American Diabetes Association recommends limiting protein intake to 10 percent of your calories.
Dangers of High-Protein Diets
The dangers of a high protein diet may be dependent on the source of protein -- it's not the protein that can cause problems, but the large amounts of saturated fat and cholesterol in animal protein that may cause health problems. The saturated fat consumed on a high-protein diet may be double or triple the amount recommended by the American Heart Association, which says that no more than 10 percent of your calories should come from saturated fat. However, high-protein diets that are plant-based and include large amounts of legumes, nuts and soy products do not have the same levels of saturated fat.
High-protein/Low-carbs
Many high-protein diets also restrict carbohydrates. Although limiting sugars and refined flours may be beneficial for health and promote weight loss, restricting high-fiber plant based vegetables and legumes is not healthy. Johns Hopkins Medicine notes that high-protein, low-carbohydrate diets raise risks of heart disease due to low fiber. The Atkins and Protein Power diets only provide between 5 to 10 g of fiber, far below the American Diabetes Association recommendation of 25 to 30 g.
References
- Harvard School of Public Health: The Nutrition Source -- Protein
- Atkins Diet Alert: health Advisory
- American Heart Association: High-Protein Diets
- Johns Hopkins Medicine: The Dangers of High-Protein, Low-Carbohydrate Diets for People With Diabetes
- MayoClinic.com; Are High-Protein Diets Safe for Weight Loss?; Katherine Zeratsky, R.D., L.D.; June 19, 2010
Member Comments