Discover why countless studies show people who go plant-based manage to lose weight fast
January 2021
By Alex White
We tend to eat a similar amount each day so what we eat makes a big difference. For example, someone who burns 2,200 calories and eats four pounds of food a day needs a mix of food averaging 550 calories per pound to maintain their weight. This is called the ‘calorie density’ of their food and many experts argue that, while it is only one piece of the puzzle, it plays a crucial role in weight control.
Figure 2 (below) gives some examples to bring this to life. Each column shows a different diet someone could eat. For each case we’ve assumed the person burns 2,200 calories a day and needs four pounds of food to avoid feeling hungry. Once you’ve read it, we’ll discuss each diet in turn.
First, let’s look at the Standard American Diet which is high in meat, fat, sugar, and processed foods. These foods tend to have quite a high calorie density (typically a thousand calories per pound or more). Still, we’ve assumed this person is also eating some heathier foods as well, leading to an average of 900 calories per pound. Even with this low estimate, the problem is clear. By the time they satisfy their hunger with their daily four pounds of food this person has blown through their calorie limit for the day. In fact, their ‘energy balance’ is a whopping 1,200 calories over their calories burned. At this rate, they are sure to gain weight fast.
Second, there’s a typical weight loss diet. Here, some healthier choices bring the average calories per pound down a bit (to 600 in this example). But, the usual advice to count calories and watch portion sizes still leaves our dieter with a big problem: hunger. By the time they hit their calorie limit (1,800 in this case) they’ve only eaten three pounds of food. Their only option then is to be ‘strong’ and go hungry. This is both miserable and unnatural. What’s natural is to give in – which is why most diets fail.
Third, we have a standard whole-foods, plant-based diet. Here the goal is keeping a steady weight. The solution is simple: match the food we eat to the energy needs we have, without eating less. In this case that means eating a diet with about 550 calories per pound – which is only possible by emphasizing minimally processed, plant-based foods. By doing so this person can eat the four pounds of food they need to feel full while getting no more or less than the 2,200 calories they need for the day. The beauty of this is that it is sustainable.
Fourth, we have a whole-foods, plant-based diet for weight loss. This is basically identical to number three, but the person has chosen to focus a bit more on low calorie density foods like fresh fruits and vegetables. They’ve also cut out oil. That’s because all oil – even the much-hyped extra virgin olive oil – is 100 percent fat. That gives it about 4,000 calories per pound and makes it a great food to cut out of your diet if you’re watching your weight.
Figure 3 (below) shows how much calorie density varies across different foods. You’ll notice how oil is about 40 times more calorie dense than most vegetables. It’s also worth noting that the most calorically dense foods tend to be either animal products or processed foods. The exceptions are things like tortillas, dried fruit, bread, nuts and seeds. These foods all have a place in a healthy plant-based diet, but we need to watch out for both quantity and quality when we eat them.
If you’d like more information on this topic, both the CDC and healthline.com have good overviews of it on their websites. You might also check out a YouTube video called “The Importance of Calorie Density & Exercise” by Garth Davis MD – one of the growing community of doctors promoting lifestyle medicine and plant-based eating that inspired us to start this program.