Plant-based diets are soaring in popularity. Unlike a vegan diet where the focus is on abstaining from meat and dairy, a plant-based diet focuses on what you ADD to your diet – healthy, plant-based foods, lots of fruits and vegetables. Not only are fruits and vegetables nutrient-rich, but they also contain a wealth of phytochemicals that meat and dairy foods lack. These phytochemicals are mildly toxic to the body but stimulate a protective response that’s beneficial to health. It’s similar to the way exercise stresses the body but, ultimately, makes it stronger. Phytochemicals in plants turn on the body’s natural defenses against oxidative stress and other threats, giving cells greater ability to clear toxins and subdue cellular threats.
In addition to the unique phytochemicals in plants, plant-based foods are also lower in calories. Plus, many plants are high in water and fiber, making them satiating but also less likely to cause weight gain. It’s a win-win situation. You enjoy nutrient-dense plants without lots of calories. Knowing this, you might assume that plant-based diets would be helpful for weight loss. A recent study published in the Journal of the American College of Nutrition put this idea to the test.
Is a Plant-Based Diet More Effective for Weight Loss?
In a study, researchers divided type 2 diabetics into two groups. Each group ate a lower calorie diet containing 500 calories less than the required for maintenance, although the composition differed. One group ate a diet consisting exclusively of plant-based foods, essentially a vegetarian diet, while the other ate a standard diabetes diet. At the end of six months, they compared weight loss and body composition between the two groups.
The results? The participants that ate the vegetarian diet lost almost twice as much as weight as those who ate the standard, diabetes diet. In fact, the vegetarian group shed 13.67 pounds while the non-vegetarian diet group lost only 7 pounds. The vegetarian group also lost more sub-fascial fat and intramuscular fat than did the non-vegetarian group. That’s significant because fat stored within the muscle worsens insulin resistance. Studies link higher quantities of intramuscular fat with abnormal blood glucose and lipid levels, independently of body weight.
The results of this study aren’t surprising. A number of studies correlate plant-based diets with a lower body mass index as well as less risk of weight gain with age. In fact, a 2006 meta-analysis of 87 studies linked plant-based diets (vegetarian and vegan) with greater weight loss as well as a lower risk of type 2 diabetes, heart disease, high blood pressure, and obesity.
When you consider the composition of plants – their high fiber and water content – the results of the study makes sense. Fiber and water expand within the digestive tract and slow stomach emptying. This, in turn, suppresses appetite. Some studies also show that plant-based foods boost the thermic effect of food, the additional calories you burn after a meal to digest, absorb, and process the food you ate.
The Drawbacks of Going Completely Plant-Based
So much for the positive – but are there drawbacks to going plant-based such as the risk of nutritional deficiencies? It’s possible to eat at a nutritionally balanced diet that’s completely plant-based, although it takes a little planning to meet all of your body’s nutrient and micronutrient requirements. Vegans who eliminate all animal products are at risk of vitamin B12 deficiency. However, that can be remedied by supplementing with vitamin B12. Depending upon the composition of a plant-based diet, getting enough calcium and zinc can be an issue too.
Fortunately, packaged foods like plant-based milk, orange juice, and non-dairy yogurt are often fortified with calcium. Although zinc is most abundant in animal foods, pumpkin seeds are one of the richest plant-based sources of this mineral you need for immune health and wound healing. In fact, a quarter cup of pumpkin seeds supplies almost 20% of the day’s recommended zinc intake. Oatmeal and cashews are other excellent sources of zinc.
What about the issue of getting enough protein? Not all plant-based foods are a complete source of protein. Some lack one or more essential amino acids that your body needs and can’t make. However, by eating a diverse plant-based diet, you can get the full spectrum of essential amino acids. Soy, quinoa, and amaranth are three plant-based foods that have all the essential amino acids your body needs and can’t make on its own.
Another Advantage of Eating More Plants
Eating more plant-based foods also works well for people who don’t enjoy calorie counting, a practice that requires lots of discipline and the merits of which are being questioned. The mantra now is to focus on diet quality and a plant-based diet is one that’s nutrient dense rather than cutting calories. The calories you eat creates a metabolic environment that impacts how your body processes glucose and whether it burns as energy or stores what you eat as fat. No one can deny that equal calories of a sugary pastry and a bowl of non-starchy vegetables have a very different impact on the hormonal milieu within your body. When you eat a diet rich in plants, you’re getting food in its unaltered state and in a form that’s nutrient dense.
The Bottom Line
You don’t necessarily have to go vegan or even vegetarian to get the benefits of a plant-based diet. You can get substantial perks by simply adding more plants to your diet. Choose more plant-based sources of protein as well. At the same time, eliminate processed foods. The problem with some vegan and vegetarian diets is the focus is solely on not eating meat rather than choosing whole food, non-animal sources.
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