No doubt you’ve heard the awards for the Mediterranean Diet. This plant-rich diet, which allows for some animal products (such as low-fat cheese, fish, and lean protein), has been hailed as the best diet for long-term health. But here’s the million dollar question: how does the Mediterranean diet compare to a vegan or plant-based diet for overall health and weight loss?
A new study from the Journal of the American College of Nutrition provides the answer. As it turns out, not all plant-based diets are created equal. If you want to achieve weight loss and optimal health, eating plant foods is the answer.
Comparison of the two diets: Mediterranean and plant-based or vegan
The Mediterranean diet and the vegan diet have a lot in common, namely that they are both high in fruits and vegetables and high in fiber. However, there are major differences.
Whilst vegan or plant-based whole foods eliminate animal products, a Mediterranean diet only limits them, explains Dr. med. Hana Kahleova, co-author and director of clinical research for the Medical Committee for Responsible Medicine. A vegan or plant-based whole food diet is also low in fat. Higher fat foods like oils, nuts, and seeds are also common in a Mediterranean diet.
How could these diets affect health traits such as weight, cholesterol, blood pressure, blood lipids, and insulin sensitivity? That is the question that drives researchers, especially given that the Mediterranean diet has been touted not only for heart health, but also for its effects on weight loss.
The results of this new study: A vegan or plant-based diet is better for weight loss
Kahleova and her colleagues recruited 62 people with no history of obesity and randomly assigned them to vegan or Mediterranean diets, none of which had calorie restrictions, for 16 weeks. Those who followed a vegan diet were asked to eliminate all animal products, keep oils and added fats low (limited to 10 percent of daily caloric intake), and base their diet on fruits, vegetables, grains, and legumes. “From there, they could eat and eat the foods they enjoyed until they felt full without counting any calories,” she says.
In the meantime, the Mediterranean diet group ate not only these foods but also low-fat dairy products and extra virgin olive oil. In addition, they limited themselves (to one serving per week or less) or avoided red meat and saturated fats, and were asked to limit or eliminate cream, butter, margarine, processed meats, sweetened drinks, pastries and processed snacks.
After 16 weeks, study participants resumed their previous diets for four weeks before switching to the other diet for 16 weeks. The results? Unsurprisingly, the vegan diet has won over almost all health measures. “We expected positive results from the low-fat, plant-based (vegan) diet, knowing that previous studies have shown that plant-based (vegan) diets are great for improving these health markers,” says Kahleova.
How and why did the vegan diet surpass the Mediterranean diet
For starters, take weight loss and body fat. People on a plant-based diet not only lost about 7.5 pounds more fat, they lost an average of 13 pounds while the Mediterranean diet didn’t change much. The visceral fat, the poisonous fat between the organs, also decreased more strongly with the vegan diet. And while there were no significant changes in cholesterol on the Mediterranean diet, the vegan diet did reduce total and LDL cholesterol (also known as bad cholesterol).
There are good reasons to explain the extent of the difference between the two diets. “A vegan diet is low in fat and high in fiber, which means you will feel full with fewer calories,” says Kahleova. On the other hand, higher energy foods like fish, chicken, and higher fat plant foods like oil and nuts won’t fill you as much. “This, in part, likely resulted in less weight loss on the Mediterranean diet.”
The blood pressure, which decreased on both diets, decreased a little more on the Mediterranean diet. The researchers aren’t sure why, but say sodium levels in individual participants’ diets may have played a role, as did olive oil. “It was thought that olive oil may help lower blood pressure because of its high levels of vitamin E and polyphenols,” says Kahleova. Just don’t take this as a license to indulge in olive oil. “People need to be careful with olive oil as it is energy dense and may not promote weight management and other cardiometabolic risk factors and a low-fat vegan diet.”
If you want to lose weight and get healthy, this study recommends: Go vegan or plant-based
While this study clearly demonstrated that the vegan diet had numerous advantages over the Mediterranean diet, it also showed that the Mediterranean diet is not all that matters. “People who really need help – with weight or other health problems – are often misled into believing that a Mediterranean diet is most effective,” says Kahleova, adding that studies of the Mediterranean diet often lead to exercise or calorie restriction, which the effects of diet change could distort the effects.
Kahleova points to the Lyon Diet Heart Study, which found that a Mediterranean diet resulted in three pounds of weight gain rather than weight loss during that two-year study. In this study, which first popularized the Mediterranean Diet in 2001, all participants, 90 percent of whom were overweight, followed a Mediterranean diet supplemented with either extra virgin olive oil or nuts. During the first three months, the weight loss in the olive oil group was less than half a pound and in the nut group a little more than half a pound. The main benefits were related to general health and particularly cardiovascular health.
Do you want to switch to a vegan or plant-based diet all the way? Follow study participants’ activities and test weight loss options while eating healthy whole foods. Remember the plant-based foods you already enjoy – oatmeal for breakfast? Chilli with black beans for dinner? – as well as new dishes that you may want to try for three weeks and include in your daily diet. With no calorie counting or carbohydrate restrictions, it’s easy to do and you can discover new foods and flavors. You will be surprised that you love it. “People often find it a lot less restrictive [to go plant-based] than you might have imagined, ”says Kahleova.
“Many people begin to lose weight within three weeks, feel energizedand improve other health markers, often encouraging them to stick to a plant-based diet longer. “