«Consuming acid-producing foods such as meat, eggs, and dairy products can increase the acid load in the diet, or the amount of acids consumed, causing inflammation related to weight gain,» explains Hana Kahleova, director of clinical research at the Physicians Committee and lead author of the study.
«But replacing animal products with plant-based foods like leafy greens, berries, and legumes can help promote weight loss and create a healthy gut microbiome,» she adds.
This new research, published in the journal ‘Frontiers in Nutrition’, included 62 overweight adults who were randomly assigned to a Mediterranean diet or a low-fat vegan diet for 16 weeks, separated by a four-week washout period, followed by an additional 16 weeks on the alternate diet.
Participants’ dietary records were used to calculate the acid load of the diet, which is typically estimated using two scores: Potential Renal Acid Load (PRAL) and Net Endogenous Acid Production (NEAP). A higher score indicates a higher acid load in the diet.
Animal products, such as meat, fish, eggs, and cheese, cause the body to produce more acid, increasing the acid load of the diet, which is linked to chronic inflammation that disrupts metabolism and can lead to weight gain.
Plant-based diets, which are more alkaline, are associated with weight loss, improved insulin sensitivity, and lower blood pressure.
In the new analysis, both PRAL and NEAP scores significantly decreased with the vegan diet, with no significant changes with the Mediterranean diet.
Reducing the acid load of the diet was associated with weight loss, and this association remained significant even after adjusting for changes in energy intake. Body weight decreased by 6 kilograms with the vegan diet, compared to no change with the Mediterranean diet.
The authors suggest that the alkalizing effect of the vegan diet, which raises the body’s pH level to make it less acidic, may also contribute to weight loss.
Among the top alkalizing foods are vegetables, especially leafy greens, broccoli, beets, asparagus, garlic, carrots, and cabbage; fruits, such as berries, apples, cherries, apricots, or melon; legumes, including lentils, chickpeas, peas, beans, or soy; and grains, like quinoa or millet.
Founded in 1985, the Physicians Committee for Responsible Medicine conducts clinical research and advocates for stricter standards of ethics and efficacy in education and research.