In light of Paleo's low ranking in US News & World Report, it stands to reason why most RDs don't advocate the diet—and for a variety of reasons. "The Paleo diet has a lot of good things going for it. It recommends excluding processed foods and refined sugars and emphasizes fruits, vegetables, nuts, seeds, and lean protein," says Heather Mangieri, MS, RDN, CSSD, LDN, a spokesperson for the Academy of Nutrition and Dietetics and author of Fueling Young Athletes. However, Mangieri says, "Any diet that suggests eliminating an entire food group can set you up for nutritional deficiencies, boredom, and an overfocus on food." Because the diet eliminates all dairy, meeting calcium and vitamin D requirements can be difficult. Mangieri has experienced this issue firsthand in her private practice. "Even though Paleo proponents claim they can meet their calcium needs from nondairy foods, I have yet to find a client that eats that many greens and is that thought out in their eating. Supplementation becomes a must to meet the needs for these nutrients."
A vegetarian or vegan diet can be a good choice for people with diabetes. Vegetarian and vegan diets are typically high in carbohydrates - about 13% higher than a diet with that includes both plant and animal products (omnivorous) – which we generally think is bad for diabetes. However, a vegetarian or vegan diet is typically higher in fiber and lower in calories and saturated fat, so the inflammatory risks associated with high meat consumption are avoided. Research studies that have tested vegetarian and vegan diets for people with diabetes; have found them to be beneficial at reducing blood sugar.12
Perhaps the biggest benefit of this type of diet is the potential for weight loss, given that currently over 70 percent of the United States population is either overweight or obese, according to the NIDDK. The NIDDK reports that people who initially lost 15 to 25 percent of their body weight within six months might be able to maintain a 5 percent weight loss over a period of four years. (2) The catch here is that exercise and permanent lifestyle changes must be made for such effects to stick — and there’s no evidence the military diet leads to sustainable healthy habits that result in maintainable weight loss.
“Crash diets, also called meal-replacement programs, have become increasingly fashionable in the past few years,” said lead author Dr. Jennifer Rayner, Oxford Centre for Magnetic Resonance, University of Oxford, Oxford, UK. “The metabolic improvements with a very low-calorie diet, such as a reduction in liver fat and reversal of diabetes, would be expected to improve heart function. Instead, heart function got worse in the first week before starting to improve.”
Saturated fat and trans fat are the main dietary culprits in increasing your risk of coronary artery disease. DASH helps keep your daily saturated fat to less than 6 percent of your total calories by limiting use of meat, butter, cheese, whole milk, cream and eggs in your diet, along with foods made from lard, solid shortenings, and palm and coconut oils.