Myths of the High Protein / Low Carbohydrate Diet
By John Hoeber, MS, RD

Proponents of high protein/low carbohydrate diets claim that they are good for weight loss, sports performance and health in general. There are only a handful of doctors, biochemists and nutritionist who support this view. Conversely, most of the scientific and medical community believes the opposite.

Myth #1: High Protein Diets are Good for Weight Loss
Actually this is true as it is true for all structured diets, they will cause weight loss. They are very low calorie (1000-1500) and disrupt normal eating patterns. Unfortunately they do not result in great amounts of fat loss and the weight that is lost is quickly regained because the dietary restrictions are very hard to maintain.

Most of the initial weight loss is from water. Low carbohydrate diets cause a depletion of the body’s stores of carbohydrate (glycogen). This will cause water loss as glycogen, (carbo-hydrate), is stored with water (3 grams of water for every gram of carbohydrate in glycogen). As the diet continues ketones, dangerous waste products of protein breakdown, accumulate in the blood, forcing the kidneys to increase urine output to get rid of them.

What these diets are good at is getting people to avoid common snack foods such as pastries, bagels, chips, cookies, etc, which are often eaten in excess and cause weight gain. Carbohydrates are not bad for us if we eat the right kind (unrefined, whole wheat breads and pasta, brown rice, legumes, fruits and vegetables), in proper amounts (un-supersized). Eaten in this way carbs do not cause a spike in blood insulin levels that can increase hunger and fat storage.

Since weight loss is still governed by a balance between calories ingested and expended we cannot talk about diets without also mentioning exercise. Being sedentary, like most Americans, decreases carbohydrate metabolism and increases weight gain from eating high carbohydrate diets. The more we exercise the better we become at storing and using carbohydrate effectively. Without also manipulating exercise levels, weight loss efforts will be futile.

Myth #2: High Protein/Low Carbohydrate Diets are Good for Sports Performance.
This theory is totally without support. Every good study on endurance athletes shows that a high carbohydrate diet increases sports performance. Proponents argue that high pro/low carb diets make an individual better at accessing fat stores for energy, but this is a function of fitness level not diet. The fitter the individual the better they can cycle carbohydrates and fats in and out of storage for use as energy.

Myth #3: High Protein/Low Carbohydrate Diets are Good General Health.
This theory also flies in the face of scientific evidence and the positions of nearly every major health organization.
-High saturated fat intakes raise cholesterol and rates of heart disease and stroke
-High protein intakes create negative calcium balance raising the risk of osteoporosis
-High intakes of meat products raise the risk of several cancers
-Low intake of fiber raises the risk of colon cancer
-High protein intakes can increase kidney damage and the risk of kidney stones
-High intake of animal fat creates and eicosanoid balance that promotes inflammation and blood clotting

If we look at diet around the world we find that the more affluent, meat based diets cause the most obesity, heart disease and cancer. In places where vegetarian or starch based diets predominate we find that people are leaner and healthier. Carbohydrates are not to blame for our weight gain, but rather how we eat them (refined and supersized), and what we do (or don’t do) with them - exercise.