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High Protein, Low Carbohydrate Diets

 (e.g. Atkin's Diet, The Zone, Sugar Busters, Protein Power)

High protein diets are based on the mistaken assumption that carbohydrates are responsible for weight gain. Since chips and candies tends to cause weight gain, and these foods contain lots of carbohydrates, they are believed to cause weight gain. Therefore, these diets encourage people to load up on proteins and avoid carbohydrate as much as possible.

People on high protein diets notice a very quick, very dramatic weight loss, but inside the body...
  • The liver stores excess glucose as glycogen which is released when needed. When the liver runs out of glycogen, the body thinks it is being starved and starts breaking down muscle and internal organs to produce glucose and fat to release ketones as an alternate source of energy. 
  • When ketones are released it causes ketosis which can lead to dehydration, dizziness, constipation, headaches and kidney stones.
  • The more protein someone eats, the greater the concentration of nitrogen and urea in the blood.
  • Because the body needs to rid itself of excess ketones and urea, people sweat and pee more often which results in dehydration and a lower body weight. 
While this is happening, the body is being exposed to greater health risks...
  • The brain can't use ketones effectively as fuel therefore when it doesn't get enough glucose from carbohydrates, it causes slower thinking and reaction times.
  • Certain muscle groups responsible for fast, repetitive motions (e.g. hands) can't use ketones for fuel, therefore you'll experience decreased speed and endurance .
  • The kidneys are overworked trying to get rid of ketones and urea which can result in permanent damage to the kidneys or kidney failure.
  • High protein diets are usually also high in saturated fat which increases the risk of heart attack and stroke.
  • Large amounts of protein can take calcium away from your bones causing osteoporosis.
          Although some studies have shown that these diets can result in short-term weight loss, they screen out participants predisposed to risk factors, don't take into account their exercise regiment, and excluded those who weren't able to complete the study due to the adverse side effects.  There have also been no long-term studies about health risks or whether people were able to keep the weight off.  Since high protein, low carbohydrate diets contradict a lot of the healthy eating guidelines, Registered Dietitians don't recommend that students follow this plan of eating.
Adapted from Understanding Normal & Clinical Nutrition (Whitney, Cataldo & Rolfes, 1994), Ask the Dietician, and the American Dietetic Association.


Queen's Heath, Counselling and Disabilities Services

Queen's Heath, Counselling and Disabilities Services, Queen's University