Will a low-carb vegetarian diet help with weight loss?

by | Mar 10, 2020 | Last updated Feb 15, 2022

Low-carb diets have been around in one form or another since the 1960s. But they’ve seen something of a renaissance in recent years, with newer diets like Atkins, the ketogenic diet, and low-carb paleo diets making waves. And while low-carb eating has plenty of anecdotal support, it’s a controversial topic among doctors. 

Generally, low-carb dieting means you have a daily allotment of carbohydrates (anywhere from 20-150 grams), but you are otherwise unrestricted in the amount of food you can eat in a given day. The diet is particularly attractive for people who struggle with giving up snacks. (Who wouldn’t want to chow down on high-fat treats while shedding pounds?) And for people who also want to cut out meat – for ethical, health, or environmental reasons – a vegetarian low-carb food plan is surprisingly easy to put together.

But does low-carb dieting really work for weight loss, or is it just another fad? Let’s explore how these diets work and what the research really says about low-carb vegetarian eating.

Benefits of a low-carb vegetarian diet

Plant-based diets, when planned thoughtfully, can help you lose weight and feel healthier. Extensive population studies have shown that people who follow a vegetarian or vegan diet tend to live longer and suffer lower cancer rates. 

Some research has shown that low-carb diets are more effective for weight loss than low-fat dieting, though other research shows similar effects. They’ve also proven better than low-fat and Mediterranean diets at lowering triglyceride levels (a “bad” form of cholesterol that you want to keep as low as possible) and boosting HDL (the so-called “good” cholesterol). A plant-focused, low-carb diet has also been associated with lower the risk of heart disease and lower the risk of diabetes. (Note that these benefits did not apply to low-carb eaters whose diet was high in animal fat and protein.)

You may also find that there are additional health benefits to low-carb dieting. The habits you develop while moderating carbs can be valuable, like adding more fruits and vegetables to your meals and paying closer attention to portion size. Even if you end up dropping the low-carb diet, these are helpful habits you might stick with.

This all sounds pretty good, doesn’t it? So what’s the catch? Unfortunately, when it comes to low-carb vegetarian dieting, there are several drawbacks to be wary of.

Risks of a low-carb vegetarian diet

Low-carb vegetarianism – especially when you’re getting started – is a planning-intensive diet program. You need to think carefully about what you’re eating, watch your daily carb counts, and (when possible) cook meals in advance. Otherwise, you’re likely to fall back on the same crutches other dieters rely on: processed foods, junk foods, and expensive meals from specialty restaurants. Vegetarians also need to be careful to ensure they get sufficient vitamins and minerals. Many plant-based eaters take iron, B-12, Vitamin D, and omega-3 supplements for just this reason.

You should also know that carbohydrates aren’t all bad! Carbs are your body’s primary source of glucose, which is essential for a healthy nervous system. Studies have shown that people who undergo long term carb restrictions have increased risks for certain heart problems. And diets too high in protein (which is a possibility if you’re eating low-carb) can also cause kidney problems. More immediately, active people on low carb diets may notice a dip in their usual energy levels. As your body gets used to metabolizing fats, you may see your energy return – but until then, be careful about strenuous exercise.  

There are also serious questions about the long-term efficacy of low-carb dieting. According to the Mayo Clinic, “most studies have found that at 12 or 24 months, the benefits of a low-carb diet are not very large.” In other words, despite the fact that the low-carb diet is generally regarded as a safe short-term weight loss strategy, it’s not clear that it will help you stay at your goal weight.

If you are pregnant, a low-carb diet is probably not a good idea, as it can seriously increase the risk of birth defects in your baby. Talk to your doctor about the best foods to eat to ensure a healthy amount of weight gain for your pregnancy. And of course, if you’re affected by health conditions like diabetes, it’s vital to follow all of your doctor’s recommendations about carb intake and develop a weight loss plan that is safe for you. 

Foods to avoid on a low carb vegetarian diet

When you’re planning your meals, you’ll have to get in the habit of reading the nutrition facts on everything you purchase, regardless of what it says on the front of the package. Be prepared to measure out your portions, so you know exactly how many carbs you are ingesting with each meal or snack. You will need a food scale and measuring cups to get this right.

You’ll also need to do a little math to get an accurate count because your body won’t treat all the carbohydrates the same. “Net carbs” refers to the total amount of carbohydrates after you subtract the fiber, since your body doesn’t metabolize the calories in fiber. For instance, a cup of cauliflower has 5 grams of carbohydrates, with 2 grams of fiber, so it has 3 grams of net carbs. (Hence the popularity of riced cauliflower and those tasty cauliflower pizza crusts!)

Of course, not everything has a nutrition label, so you will need to log your food using Noom’s extensive food database. But in general, fruits and starchy vegetables, like potatoes, will be too high in carbs to eat with every meal. Instead, choose non-starchy vegetables, like greens and cruciferous veggies, to bulk up your meals and eat as snacks. 

If you have a sweet tooth, fruit is a much better option than sugary treats and can help you stay within your carb limits. Watermelon and strawberries are the best choices here, both for their high vitamin content and their relatively low carb footprint.

You’ll also need to be mindful of the quality of fats you’re eating. When cooking, avoid unhealthy fats like margarine or oil blends, canola, soy, and peanut oil. Stick to full-fat butter, coconut oil, avocados, and olive oil. 

Pasta, bread, and rice are too high in carbs to be a realistic choice, but there are plenty of alternatives. That includes bread and wraps made from almond flour and pasta made from lentils or chickpeas. Veggie noodles and riced vegetables are also readily available, and easy to make yourself if you have the tools.

So if you’re not eating carbs, where will all your calories come from? Mostly they’ll be from fat and protein. And great news – there are plenty of vegetarian options to choose from. Here are the best:

Hard-boiled eggs: Easy to make and take with you throughout the day as a snack, eggs have less than one carb per serving. 

Cheese: Equally good made into a sauce or eaten on its own, cheese offers all of the health benefits of milk with a much lower carb cost. 

Beans and lentils: A common staple for many plant-based diets. Because they come with a fairly high carb cost, you may only be able to eat them for one meal a day. Lentils and black beans offer the best protein-to-carb ratio.

Nuts and seeds: High in healthy fats, protein, and beneficial minerals, nuts can be eaten throughout the day when you need a snack that’s heartier than veggies. Pistachios, pumpkin seeds, and hemp seeds are higher in unsaturated fats and protein than some of the others. 

Chia seeds: Worth special mention here because of the high amount of fiber and omega-3 fats. Try out a low carb chia seed pudding recipe for a creamy breakfast meal that can replace your oatmeal!

Soy: Tofu and tempeh are both low-carb protein powerhouses that can be made into countless stir-fries and curries, or used as meat substitutes in cuisines from around the world. 

Seitan: While it has more carbs than tofu and tempeh, it also has a lot more protein. People enjoy seitan as a versatile meat substitute with an incredible texture. However, it’s not for everyone, as it can cause upset stomachs in some people.  

Protein powders: The best ones combine pea protein with a couple of other plant-based protein sources (e.g. cranberry or hemp) for easy digestion and a good balance of amino acids. 

The bottom line

Eating a low-carb diet is feasible, and it may help you with shorter-term, moderate weight loss. But in the long run, you are better off choosing higher-quality foods rather than restricting or eliminating them altogether. 

If your goal is immediate weight loss, you may get frustrated with your results and give up. But if you come into the process with a healthy mindset and realistic goals, your fitness journey will have benefits that are far greater than the number on your scale or the size on your tag. The mental and physical benefits of having a healthier, happier relationship with eating are truly profound.

Sound impossible? Noom is here to help you make it happen. Our science-driven, psychologist-designed app connects you to the resources you need, including low-carb vegetarian recipes (if that’s what you enjoy!) and your own personal health coach. Come learn about how we help you achieve long-term, sustainable weight loss.