New Study Shows That Processed Food Makes You Fat (Not Fat or Calories)

Scientists found that feeding study participants a processed diet made them gain weight, and feeding participants an unprocessed diet made them lose weight.^[1]

In other news, water is wet.

It’s easy to say, yeah, we’ve known for a long time that processed food causes you all kinds of problems, including weight gain. But this study is the first randomized controlled trial that has actually tested the effects of processed vs. whole foods in an ultra-restrictive setting.

Men and women stayed in a metabolic ward at the research facility for a full four weeks and all of their meals were provided for them. Researchers made sure each meal on both the processed and unprocessed diets contained the same amount of calories, fats, protein, sugar, salt, carbohydrates and fiber.

Participants were allowed to eat as much as they wanted. Researchers calculated that people ate over 500 more calories of processed meals, even though they rated the meals equally as appetizing as the unprocessed meals.

The result? Over two weeks, people on the processed diet gained two pounds, and people on the unprocessed diet lost two pounds. Then, they switched diets for the remaining two weeks, and experienced the same effects in reverse.

Why did processed food make people gain weight?

So, what’s behind the weight gain and loss? Two things are at play: food science and diet-induced inflammation.

Food science to make food craveable…or addictive?

Processed food companies spend massive amounts of money on recipe developers, food scientists, and research panels to achieve a quality called “craveability,” which is exactly as it sounds — the balance of flavors and chemistry that makes people want more of it.

Could you say that craveability is the same thing as addictive quality? You decide.

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Low-quality ingredients causes your body to work differently

Cheap ingredients have low nutritional quality. On top of that, cheaper foods are more likely to have toxins that cause diet-induced inflammation, which is your body reacting to your food just like it would react to an infection or to cigarette smoke. Diet-induced inflammation causes weight gain from body fat and bloat, it clogs your arteries, you end up with brain fog, you’re cranky, you’re tired, the list goes on.

How to eat to lose weight

If you want to lose weight, download the Bulletproof Diet Roadmap — an easy guide to choosing foods that will make you feel amazing, and which ones make you weak. It’s on a single page, so you can print off and stick it to your fridge. If you follow this guide, you’ll start seeing the weight drop off within days.