The Truth About Vegetarian Diets and Weight Loss

Find out the importance of protein in the healthy weight loss process and why vegetarian diets may provide the opposite of the nutrients your body needs to lose weight.

The Truth About Vegetarian Diets and Weight Loss

I’m often asked what I recommend for dieters who are looking to lose weight via a vegetarian diet. You may be surprised, but I do not recommend vegetarian diets for weight loss.

With all of the news about avoiding red meat, processed meat, etc., it is a misconception that plant-based diets are a great way to lose weight. While I do not dispute that vegetarian diets can provide a healthy body with the nutrition required to stay that way, they are not the best option for people who have broken and dysfunctional metabolisms. This is why bistroMD doesn't offer a vegetarian program option.

The importance of protein

The reason that vegetarian-and vegan diets as well-are not well suited for people looking to lose weight is that many overweight people are overweight for metabolic reasons. The process that our bodies use to turn the food that we eat into the energy that fuels our bodies is complex, and involves chemical processes that make up what we call metabolism. 

When a person’s metabolism is dysfunctional, the last thing that it needs is extra carbohydrates and fructose, two nutritional components that are typically very high in most vegetarian diet plans. The nutritional balance I have found to be most effective for treating metabolic dysfunction and for weight loss is a reduced calorie diet with 35-40% of the calories coming from protein.

It can be very difficult to get the lean protein that your body needs to retain lean muscle tissue in the weight loss process via plant sources alone. Yes, beans and rice and other sources can provide some level of protein, but not the amount of protein that I find is necessary without also increasing the level of carbohydrate eaten.  For example, if we try to get to the level of 25-30 grams of protein at a meal with beans and rice, the amount of carbohydrate present in this vegetarian source will be almost four times the amount of protein present.   

Protein is so important in a healthy weight loss process because it is broken down more slowly by our bodies during digestion. This means that protein will not lead to spikes in blood glucose in the same way that high carb foods will. Protein is also essential in helping to maintain your lean muscle mass, which is instrumental in burning excess calories and fat. Without enough protein, your body will lose muscle mass and in turn be less effective at losing weight.

The USDA recommends 51g for women and 84g for men. If you want to lose weight, our recommendations are higher than the USDA, so that you can preserve lean muscle mass and  stay feeling full longer.

Vegetarian diets can be too high in carbohydrates, though fiber can help to balance

Basically, the only difference from one diet to the next is the percentage of protein, carbohydrates, and fat allowed. In my twenty years in the practice of metabolic medicine, I do not focus on percentages of the diet of nutrients.  I focus on the grams of those nutrients present.  For weight loss, I've found that eating 100-150 grams of quality carbohydrates leads to effective weight loss. . Trying to get to of the amount of protein needed for weight loss via tofu, beans, etc. will result is a large carbohydrate load, much higher than the recommended 100-150 grams.

Some vegetarians may question my concern that vegetarian diets are too high in carbohydrates to be effective for weight loss. Vegetarian options such as beans are a quality source of plant protein. Part of a serving of beans higher carb content is offset by another nutritional quality of beans – high fiber.  While the offsetting effect is not great enough to equate to eating animal sources of protein, fiber is your friend with a vegetarian diet. 

At the end of the day, the requirements for weight loss on a vegetarian diet are relatively strict, vs normal vegetarian eating, or the standard American diet.

Losing weight on a vegetarian diet can be tricky due to metabolic factors and the nutritional knowledge that you need in order to sort through what to eat and what to avoid. Vegetarian diets are not the norm for many people who opt to use them in their attempt to lose weight. 

The logic for many of these people is that ‘I want to lose weight; I should eat salad’. In an effort to ‘go all in’, many people set themselves up for failure because of the strict nature of a vegetarian diet compared to a regular balanced diet. The restrictive nature makes it that much more difficult to stick with. We all know that a diet you quit after a week or two is about as good as no diet at all.

What to look for when doing it on your own 

If you feel a traditional vegetarian diet is right for you, don’t adopt one in an effort to lose weight. Successful weight loss is achievable for most people when a 1200-1400 calorie daily diet and following this caloric breakdown: 40-50% from protein, 30-35% from carbohydrates, and 20-25% from fat.

If you want to eat a vegetarian diet, in order to balance protein and carbohydrate ratios we recommend eating a pesca-ova vegetarian diet. It’s easier to get the protein you need, more nutritionally balanced, and less restrictive. 

I also recommend supplementing your diet with plant-based protein powders (such as: Pure Encapsulations & Life’s Basics) to help get your daily protein intake up to the 25-30 gram level for each meal.

If you want the convenience of diet delivery

If you need the convenience of diet delivery while sticking to a vegetarian diet, bistroMD can offer modified vegetarian diets. If you are willing to incorporate fish, eggs and possibly even some dairy, we can provide a modified vegetarian diet program with limited variety. 

If you need the convenience of diet delivery while sticking to a standard vegetarian diet you can find several fresh delivery programs that offer a vegetarian selection, though these offerings are not the best option for weight loss. You’ll want to watch how many carbohydrates you’re eating, and I also urge you to keep the amount of protein needed daily in mind. On average, vegetarian meal delivery services provide about 45g of protein/day. Remember: the USDA recommends 51g for women and 84g for men. 

No matter how you decide to eat healthier, make sure you incorporate high protein options and prepare to supplement with additional protein to have a nutritionally balanced diet.

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