Plant-Based Eating: Does it help with weight loss?
Takeaways
Plant-based eating discourages the consumption of meats, dairy products, and eggs.
Following a plant-based diet could help you lose weight. However, research shows it provides comparable weight loss results to any isocaloric, calorie-restricted dietary strategy—even an omnivorous diet.
Plant-based eating may benefit your health (e.g., lower risk of cardiovascular disease) and the Earth’s health (e.g., reduces greenhouse gas emissions).
A plant-based diet may not be healthier or more nutritious than other eating patterns. However, you can typically address these shortcomings by adhering to the basic principles of healthy eating.
Ultimately, ask yourself if a lifetime's worth of plant-based eating sounds enjoyable and/or doable before committing.
You’ve tried eating less. You’ve tried intermittent fasting. And, despite your deep-rooted love for carb-rich foods (Cereal! Chicken Rice! Waffles!), you’ve even given the ketogenic diet a whirl. A testament to just how far you’re willing to go to lose weight. Still, the numbers on your weighing scale refuse to budge. At this point, it may feel like you’re out of normal-ish weight loss dietary strategies (because, obviously, diets like the baby food diet are ridiculous) to try. But luckily, there's one more worth being cautiously optimistic about: the plant-based diet.
Why "cautiously"? Well, that's because, as with most dietary strategies, plant-based eating has various drawbacks. So, continue reading to learn if plant-based eating is the right way forward for you.
What is a plant-based diet?
You may be surprised to hear this, but plant-based eating, unlike veganism or vegetarianism, does not deem the following off-limits:
Poultry, meat, and fish
Dairy products (e.g., milk, butter, and cheese)
Animal products and byproducts (e.g., eggs, honey, and gelatin)
That's because plant-based eating is a regimen that encourages whole, plant-based foods and discourages meats, dairy products, eggs, and all refined and processed foods. Compare that to the definitions of a vegetarian or vegan diet:
Vegetarian diet: A diet free of poultry, meat, and fish. That said, there are many types of vegetarianism. For example, while lacto-ovo-vegetarians eat dairy foods, ovo-vegetarians avoid them.
Vegan diet: The strictest form of vegetarianism. In addition to abstaining from poultry, meat, and fish, vegans also refrain from eating all animal products and byproducts.
How does plant-based eating fare as a weight loss strategy?
Now, let’s dig into the (excuse the pun) meat of the article. Can plant-based eating help you lose weight? A large body of evidence indicates an overwhelming “Yes”. But plant-based eating is not just another diet fad.
Plant-based eating can help you lose weight
Take this 2020 meta-analysis of 22 studies investigating the effect of plant-based eating on body mass index (BMI) and weight, for instance. The researchers concluded that, overall, a transition from an omnivorous diet—i.e., a diet that consists of both plant and animal foods—is associated with weight reduction in most subjects. In fact, 17 randomized controlled trials (RCTs) out of the 22 analyzed studies found that plant-based eating led to a more significant weight reduction than an omnivorous diet.
But there’s nothing “revolutionary” about how it works
Before you take that as definitive proof that plant-based eating is better than an omnivorous diet for weight loss, note that those RCTs did not equate total calories eaten between groups. And guess what researchers found in the RCTs that accounted for calorie intake? That's right: "traditional" omnivorous, calorie-restricted diets help reduce body weight as much as plant-based eating. Meaning? There's nothing "magical" or "groundbreaking" about how plant-based eating induces weight loss.
Ultimately, it helps you lose weight the same way any calorie-restricted diet does: by helping you eat fewer calories than your body burns. While it can be argued that a plant-based diet is more advantageous for weight loss because it’s rich in satiating fiber, which could help an individual better stick to a calorie deficit, the truth is that the same can also be said about a diet rich in animal protein.
Several studies have consistently found that when calories are equated, high-protein (which is animal-derived) and high-fiber diets generally lead to comparable weight and body fat reductions.
Plant-based eating: two sides to a coin
OK, if plant-based eating leads to roughly the same weight loss results as your typical, omnivorous diet … what's the point of switching over?
Pros of plant-based eating
Answer: beyond potentially improving your health, plant-based eating could also do wonderful things for Earth’s health.
Health benefits
Research shows that plant-based diets are associated with decreased all-cause mortality and decreased risk of obesity, type 2 diabetes, and coronary heart disease.
Cardiovascular disease: Plant-based diets are associated with a reduced risk for cardiovascular disease, including a reduced risk for ischemic heart disease and cerebrovascular disease. There’s even evidence that, when combined with exercise and stress management, adopting a plant-based diet could help reverse the build-up of fats, cholesterol, and other substances in and around the artery walls (i.e., atherosclerosis plaque).
Metabolic syndrome: Plant-based diets could help cut your risk of developing metabolic syndrome, a group of risk factors, including high blood pressure, high blood sugar, elevated cholesterol levels, and abdominal fat, by 50%.
Type 2 diabetes: Research consistently shows a lower diabetes prevalence amongst individuals following a plant-based diet (compared to those on an omnivorous one). Beyond showing promise in preventing type 2 diabetes, plant-based eating also appears beneficial in the treatment of the condition. According to a 2014 meta-analysis published in Cardiovascular Diagnosis & Therapy, researchers concluded that plant-based diets could help reduce HbA1c levels, suggesting that they may help with the management of type 2 diabetes.
Environmental benefits
If you wish to lighten your ecological footprint on Earth, plant-based eating (versus a "traditional" omnivorous diet) is the way to go. Just look at the following statistics:
Greenhouse gas emissions: According to a 2016 study published in the Proceedings of the National Academy of Sciences, a global shift to a plant-based diet could reduce greenhouse gases (i.e., gases in the Earth's atmosphere that trap heat) caused by food production by 70% (!) by 2050.
Land use: Food production contributes to 80% of deforestation and, in turn, devastating biodiversity loss. Fortunately, studies show that transitioning to more plant-based eating patterns could reduce diet-related land use by 76%.
Water conservation: A 2015 study published in Science of The Total Environment found that reducing animal intake could reduce global water use by 14%. Also, the shift toward plant-based eating may help improve water quality by reducing eutrophication (the process in which a water body becomes overly enriched with nutrients, leading to excessive growth of simple plant life) caused by runoff from animal feeds and manure.
Cons of plant-based eating
There are two primary cons associated with plant-based eating:
Not all plant-based eating patterns are healthy: There are many ways to structure a plant-based diet, and the truth is that not all are equally beneficial to your health. For instance, this 2022 study that was published in The Lancet Planetary Health. The researchers found that plant-based diets higher in whole grains, fruits, vegetables, nuts, legumes, vegetable oils, and tea/coffee are associated with lower chronic disease risk, while plant-based diets high in sugar-sweetened beverages, fruit juices, refined grains, potatoes, and sweets/desserts are associated with an increased risk of chronic disease.
Nutrient deficiencies: Many studies link plant-based diets to deficiencies in key nutrients, including (complete) protein, vitamin B12, vitamin D, and DHA—which are all essential for optimal health and well-being:
Vitamin B12: Involved in developing red blood cells, plus maintaining nerves and normal brain function.
Vitamin D: Helps your body absorb and retain calcium and phosphorus, which are critical for bone health.
Docosahexaenoic acid (DHA): An essential omega-3 fatty acid that’s important for normal brain development and function.
That said, these cons aren’t insurmountable. With adequate nutritional knowledge and proper planning, a plant-based diet can be healthy and provide your body with all the nutrients it needs. In general, this would mean:
Building your diet around minimally processed, whole foods, like whole grains, fruits, vegetables, legumes, nuts, and healthy oils
Prioritizing plant-based proteins, like tofu, tempeh and other soy products
Potentially taking vegan supplements for vitamins and minerals (e.g., vitamin B12 and vitamin D) you may fall short on when eating a plant-based diet
Limiting your consumption of refined, processed carbohydrates, sodium, added sugars, saturated fats, trans-fats, and ultra-processed foods in general
Enjoyment is key to long-term sustainability
Bottom line? Yes, switching over to plant-based eating could help you lose weight. But it's important to note that the weight you'd lose is likely comparable to what you'd see with any isocaloric, calorie-restricted dietary approach. So, to decide if plant-based eating suits you, ask yourself honestly if you can tolerate significantly paring back your consumption of animal and animal byproducts over the long term.
After all, if sticking to a plant-based diet for a lifetime makes you go, “Ugh”, then you’re better off finding an alternative. But what about its health benefits? And positive environmental impacts? Here’s the truth: simply managing a healthy weight can lower your risk of mortality, metabolic syndrome, type 2 diabetes, and cardiovascular disease, too. Also, there are so many other ways you could help save the Earth, like traveling responsibly, reducing waste, and watching what you buy.
OK, but what happens if:
You try plant-based eating, and your weight still doesn’t budge?
You decide that plant-based eating isn’t for you … what now?
In that case, you might want to stop trying different dietary strategies for size … and target what's inside you instead: your genes. That’s because, as it turns out, studies suggest your genes may determine up to 80% of your weight. And don’t worry. You won’t need to get your hands on CRISPR technology.