Top 5 physician-recommended diets

There are a million different diets out there, so there’s enormous confusion, innumerable mixed messages, and utter bewilderment when it comes to understanding which one to follow for optimizing long-term health.

“Ask your doctor” is the boilerplate recommendation in pharmaceutical ads. So, since food is medicine, why not ask doctors about which diet they recommend? That’s what Sermo (a social platform for physicians and a healthcare data collection company) recently did when it surveyed 515 US physicians across 27 specialties.

According to the survey, these are the top five diets that doctors recommended, counting from number five up to number one: 

5. Ketogenic 

Only 1 in 20 doctors (5%) who were surveyed recommended the ketogenic diet as the best for long-term optimal health.

The ketogenic—or keto—diet is very low in carbohydrates, moderate in protein, and very high in fats. By starving the body of carbs, the diet forces the body to burn fats as its main fuel. After a few days of strict dieting, the metabolism switches into a state of ketosis, in which it burns up fats at a high rate. The fats are then converted into fatty acids and ketone bodies, which are used as energy in place of the missing glucose (previously obtained from carbs). This is what gives the keto diet its reputation for fat-burning weight loss. 

Researchers have shown that the ketogenic diet can accelerate weight loss for the short term—and that’s what it’s meant for. Accordingly, 20% of doctors surveyed recommended this diet for short-term weight loss, compared with only 5% who recommend it for optimal health. 

4. Vegan 

Only 6% of physicians surveyed recommended a vegan diet for long-term health. Perhaps that’s not surprising, given that the vegan diet is strict, allowing only plant-based foods and excluding all animal-derived foods, including fish, eggs, and dairy. 

Besides being strict and somewhat difficult to adhere to, the vegan diet can result in deficiencies in certain nutrients due to the narrower range of food options. Researchers have found that vegans can be deficient in vitamins B12 and D, calcium, iron, and essential amino acids that typically come from animal-based protein.

Then again, a vegan diet has its benefits, including improvements in cardiovascular disease, cardiovascular mortality, overall mortality, hypertension, hyperlipidemia, obesity, type 2 diabetes, and cancer incidence.

3. Intermittent fasting 

Despite the interest and excitement among the general public about intermittent fasting, only 7% of doctors recommend it for optimal health. 

Intermittent fasting restricts eating to certain time periods. It focuses on when you eat, instead of what or how much you eat. One popular version recommends full-day fasting on 2 non-consecutive days each week. Another suggests alternate days of fasting. Other versions allow eating only during a limited time each day—within 8 or 12 hours, for example.

In various studies, different researchers have found both good and bad results from intermittent fasting. For instance, certain types of fasting can benefit glucose control and blood pressure-lowering efforts, as well as reduce inflammation. However, because fasting causes weight loss, researchers have yet to determine whether these benefits are due to the fasting process itself or just due to weight loss. 

Intermittent fasting has also been associated with some drawbacks, such as disordered eating behaviors, disrupted sleep, decreased alertness, increased cortisol levels, higher HDL levels, and pancreatic damage. Also, certain people should avoid intermittent fasting; for instance, people with diabetes could experience hypoglycemic events. 

2. DASH 

About 1 in 6 doctors (16%) recommend the Dietary Approaches to Stop Hypertension (DASH) diet for long-term optimal health. As its name indicates, DASH’s principal goal is to lower blood pressure, largely by limiting foods with sodium. 

Developed by the National Heart, Lung, and Blood Institute, the DASH eating plan also emphasizes less added sugars, fats, and red meats than the typical American diet. It makes up for any loss in flavorful foods by recommending fiber-filled fruits, vegetables, and whole grains, as well as lean protein.

The only downsides to the DASH diet are that it can require quite a bit of meal planning in advance and that its guidelines aren’t very comprehensive (eg, is an avocado a fruit or a fat?) 

1. Mediterranean diet 

Compared with the other diets, doctors overwhelmingly (51%) chose the Mediterranean diet as their favorite one for long-term optimal health. Researchers have consistently shown that the Mediterranean diet reduces the risk of cardiovascular diseases and overall mortality.

This popular, mostly plant-based diet includes a wide range of foods without banning any food groups. Recommended everyday foods include fruits, vegetables, whole grains, beans, nuts, legumes, and olive oil, plus fish and seafood a couple of times a week. Poultry, eggs, cheese, and yogurt can be eaten in moderation, while sweets and red meat are only for special occasions. And a glass of red wine is a perfectly acceptable accompaniment to dinner.

Researchers have shown that adherence to the Mediterranean diet is tied to lower rates of obesity, diabetes, and heart disease. In one large trial, participants on the Mediterranean diet experienced greater weight loss and reductions in LDL cholesterol, triglyceride, fasting serum glucose, and fasting insulin levels than participants on low-carbohydrate or low-fat diets.

The Mediterranean diet is linked to living longer and living healthier. In one study, women who followed a Mediterranean-style eating plan were 46% more likely to age healthfully. Researchers attributed this finding to a greater intake of plant foods, whole grains, and fish, a moderate alcohol intake, and a low intake of red and processed meats.

Other findings

In addition to determining doctors’ top recommended diets, the results of the survey also showed: 

• 60% of surveyed physicians agree that high-carb diets are more harmful than high-fat diets.

• 85% of physicians think insurance companies should cover dietician visits to help educate overweight patients about proper nutrition, even if they don’t have any metabolic abnormalities.

• 80% of physicians said the high obesity rates in the United States are due to environmental factors—such as fast food, school lunches, time spent in front of the television or computer—rather than genetics (3%).

• 69% of physicians believe that more than half of US adults will be obese by 2030—a sharp increase from the current obesity rate of 40%. 

“Our genetics have not changed much in 200 years. What has changed massively is the availability of inexpensive, high calorie foods coupled with an increasingly sedentary lifestyle,” said Dr. Murali Doraiswamy, MBBS, professor of psychiatry and medicine, Duke University School of Medicine, Durham, NC, and a scientific advisor to Sermo. “Obesity will become our destiny unless we radically change our health policies, food environment, and habits.”