Some people are amazed after they go vegan. They’re eating bigger portions… but they’re still losing weight. This is great if you want to slim down, but you might be concerned whether you’re getting enough calories.
Vegans may need more calories to maintain weight—due to more fiber, water, flavonoids, and arginine in their diet (among other factors). Also, vegan portions often need to be bigger to contain the same number of calories, as many whole plant foods have a low caloric density.
Below, I’ll cover the surprising science behind why nuts and grape juice don’t cause as much weight gain as we’d expect. I’ll address whether carbs can be stored as fat. And I’ll share tips for maintaining, losing, or gaining weight on your vegan diet!
Do Vegans Need to Eat More?
When you switch to a vegan diet, you’ll probably at least feel like you’re eating more calories to maintain weight. This is for a few reasons.
One of those reasons is the high fiber and water content of many plant foods. Water and fiber don’t add calories to your diet, but they do add bulk.
Water and fiber help fill your plate and your stomach. When you consume lots of water and fiber-rich foods, like fruits and vegetables, you’re lowering the caloric density of your diet.
Caloric density is one of the most important concepts in all of weight-loss science. When you eat foods that have a low caloric density, you get full on fewer calories.
(This also means you can absolutely stuff yourself with bigger portions—and it doesn’t even result in excess calories.)
This is one of the reasons I like Nutriciously’s e-books so much, by the way. Their weight loss e-book explains the concept of caloric density better than any other source I know.
Their e-book includes pictures showing how much of this food you can eat for 200 calories, versus how much of that food. Check out my full review of their e-books here.
So, anyway—if you’re eating fiber-rich plant foods, you may feel like you’re eating more calories to maintain weight, even if you’re not. But there’s more science here to uncover.
There may actually be some legit ways that specific vegan calories do “count for less.” Let’s start by looking at nuts.
Calories From Nuts… Don’t Count as Much?
There was an interesting study from 2012 where people were told to add 70 grams of pistachios per day to their diet (400+ calories per day). But despite adding all those nuts, at the end of the 12-week study, it was found that they did not gain weight.
And there are other studies showing similar outcomes with nuts, too. Nuts don’t cause the amount of weight gain you’d expect based on calories.
Actually, Dr. Greger from NutritionFacts.org made a whole series of videos about this. And it turns out, it’s likely multiple factors coming together. And some of these don’t just apply to nuts.
Fiber and Calorie Absorption
First, the high-fiber nature of nuts (and a vegan diet overall) may result in more calories “going through you” undigested. Some calories are attached to fiber that your body can’t digest. So you don’t absorb those calories.
You just poop them out.
So that’s one possible way that a vegan diet may actually require more calories to maintain weight. We may have more calories “attached” to fiber and just passing through us, compared to non-vegans who eat less fiber.
The biggest reason why nuts were actually found not to cause weight loss was the “Dietary Compensation” theory.
Here’s the basic theory: Nuts are so filling—so satiating—that they lead us to eat less over the rest of the day.
There was a study where they gave two groups of people a smoothie each day. One group’s smoothie had blended up walnuts. The other just had walnut flavoring with oil. You won’t guess what happened.
The two smoothies had the same calories and were indistinguishable. But one thing was different. The smoothie with real walnuts made people feel much more satiated in the hours after eating it.
Satiation is not actually a case of your calories “counting less.” But it’s similar to what I wrote above about bulk and fiber. Some foods just fill you up on fewer calories.
For some reason, nuts are particularly satiating. Another satiating food I often refer to is potatoes. Bodybuilders often eat potatoes when cutting body-fat, as they’re the most satiating food in the world. So they make it easier to be satisfied on a caloric deficit.
Another interesting thing that comes to mind: Keto diets are said to be effective for weight loss especially because they’re satiating and even “appetite suppressing.” I wonder what is specifically behind that.
Arginine and Fat-Burning
Another suspected reason why nuts cause less weight gain than expected is the amino acid arginine. The explanation why is kinda crazy. It has to do with your “brown fat.”
So, there’s a type of body-fat that we have in our shoulders called “brown adipose tissue” (BAT). And it actually helps us regulate our body temperature.
When we’re in a cold environment, our BAT actually burns fat to keep us warm. There was actually a study where they just regularly put people in a cold room over a 6-week period, and they lost weight.
But it turns out, you can also boost BAT’s fat-burning power with food. It turns out that capsaicin, for example—the “spicy” molecule in peppers—stimulates fat-burning via BAT. (source)
But that’s not all. Arginine is also likely to boost BAT, leading to more fat-burning activity each day. And vegans are likely to get an unusually high amount of arginine in our diet.
The highest foods in arginine are soy, seeds, nuts, and beans—oh, and pork rinds (source). But most of those are whole plant foods.
So this is another possible mechanism for vegans seeing less weight gain from the same number of calories. If we’re eating those high-arginine foods—and most vegans are—then our “brown fat” is likely more active, burning more calories throughout the day.
Flavonoids = Fat-Burning Food?
Flavanoids are another interesting nutrient that could cause extra fat-burning.
Flavanoids are a type of polyphenol antioxidant. They’re super healthy—and they may help us burn more fat, too.
There was a study on concord grape juice that was pretty crazy actually. It showed that 2 cups of grape juice daily caused no weight gain… but a grape-flavored sugar drink (without antioxidants) did cause weight gain. (source)
So this is another case where the calories are not adding up the way you’d expect.
In this case, it’s suspected that polyphenol antioxidants (like flavonoids) cause extra thermogenesis and fat oxidation, leading to less weight gain.
Here are just a few foods high in flavonoids:
- Red wine
- Citrus fruit
But there are actually a ton of healthy plant foods high in different kinds of flavonoids. You can see longer lists here.
What About De Novo Lipogenesis?
If you spend time in the high-carb low-fat (HCLF) vegan community, you’ll hear this term a lot: De novo lipogenesis. And some explanations of this term can make it sound like we can eat unlimited carbs without storing body-fat.
Dr. John McDougall, author of The Starch Solution, has brought a lot of attention to this concept over the years. Some of the fruitarians picked it up and ran with it from there.
De novo lipogenesis literally means “making new fat.” It’s the process our body uses to store body-fat from excess carbs we eat.
And as Dr. McDougall explains, de novo lipogenesis is a very inefficient process. There have been studies where women were fed 150% of their maintenance calories from sugars—and they barely gained body-fat.
There may be something to this, and it could be part of why many people do see dramatic weight-loss on a starch-based diet. But I’d still caution against over-eating tons of carbs.
Carbs Can’t Be Stored as Fat?
I’m working on another blog post about why weight gain is so common on the HCLF vegan diet “Raw Till Four.”
And it’s precisely for this reason: People are instructed to eat way too many calories on the diet.
There are a lot of people who gained weight over-eating carbs due to the instruction of YouTubers like Freelee the Banana Girl and Durianrider. High-Carb Hannah is one well-know example.
What may be happening is that the fat intake of many HCLF dieters isn’t as low as they thought. Even fruits and veggies contain some amount of fat.
So there’s still plenty of dietary fat entering your body, which you store as body-fat because there are also so many carbs available.
So yeah, sure—maybe your body isn’t storing the carbs as fat… But it’s storing more of your dietary fat as fat! (source)
Even if a very high-calorie, low-carb diet worked for weight loss… it may not be safe and healthy long-term. There may be risks of forcing your body to run its de novo lipogenesis pathway on overdrive, as it was shown to do in the over-feeding studies.
Specifically, de novo lipogenesis creates fat in your liver cells. And this is thought to at least partly explain the fact that very high-sugar and high-carb diets can lead to non-alcoholic fatty liver disease (NAFLD).
Now, I’m not saying that a sensible high-carb vegan diet like the McDougall diet is going to give anyone NAFLD. I’m just saying that I’d personally be worried about over-eating thousands of calories of carbs on a regular basis. Even if you don’t seem to be gaining weight.
My takeaway message: Just be reasonable about calories and portion sizes. Don’t try to exploit a glitch in the “Matrix” of your body’s biochemistry.
How Do Vegans Get Enough Calories?
Vegans can get as many calories as they need by focusing on higher-calorie foods like nuts, seeds, dried fruit, nut butters, oils, avocados, grains, granola, and beans.
Drinking smoothies is another good strategy if you find yourself losing too much weight.
Drinking calories will allow you to consume more calories faster, so you’ll get more in before you feel full.
I listened to an interview with David Carter, an NFL player known as “The 300 Pound Vegan.” He shared his strategy to eat 10,000 calories per day. It involves drinking smoothies of fruit, oats, beans, and more—every 2 hours.
If an NFL lineman can eat 10,000 calories per day to maintain his weight on a vegan diet, so can anyone! (As long as you can afford all the food! Read my vegan on a budget post for tips on that.)
Do You Need to Count Calories on a Vegan Diet?
Most people do not need to count calories on a vegan diet. But it may help if you have a goal to maintain, gain, or lose a specific amount of weight.
Most new vegans will gradually lose some weight. I shared some specific numbers in my post “How Long Does It Take to Lose Weight on a Vegan Diet?” But it varies, of course.
For me personally, I had to start counting calories to get as lean as I wanted to. Specifically, counting calories helped me get six-pack abs.
I’ve also found it helpful to track my protein sometimes, to make sure I’m getting enough to keep making muscle gains.
But it’s not like I’d need to count calories to be healthy or just lose a little weight. It only became necessary to hit my more specific, highly targeted goal of getting a six pack.
Similarly, you may find it helpful to count calories if you want to gain weight. But it’s not completely necessary. You can also just follow some of the advice above about higher-calorie foods to eat (and listen to that David Carter interview)!
How Many Calories Should a Vegan Eat Per Day?
The ideal calorie intake for a vegan will vary based on body size, activity level, and bodyweight goals. Although vegans may have slightly different results, most standard advice about calorie counting will still apply to vegans.
If you’re going to track your calories, I recommend first using a Total Daily Energy Expenditure (TDEE) calculator to determine how many calories you burn each day.
Then, if you want to lose weight, I’d aim for a calorie intake anywhere from 200 to 700 calories below your TDEE. Since a pound of fat is roughly 3,500 calories, a deficit of 500 calories per day will average one pound of fat-loss per week.
If you’re currently obese, it may be okay to target larger calorie deficits. But if you’re already in a more moderate weight range, a calorie deficit over 700 can lead to things like hormone imbalances. It’s not worth it. Go slow and steady.
If you’re trying to gain muscle (a.k.a. “bulk”), then I’d just add 200 or 300 calories to your TDEE. This will allow you to add muscle without gaining much extra fat—if you’re doing the right strength training with it.
Two More Recommendations for Your Plant-Based Journey
1. This is the best free video training I’ve found on plant-based nutrition. You’ll learn how to reduce your risk of cancer, heart disease, type 2 diabetes, Alzheimer’s, and obesity—all with plant-based food. Watch the free “Food for Health Masterclass” here.
2. This is the best vegan multivitamin I’ve found in my 14 years of being vegan. It has vitamin B12, vitamin D, omega-3—and nothing else. Translation: It only has the nutrients vegans are actually low in. Read my full review of Future Kind’s multivitamin here (with 10% discount).