The Protein Leverage Hypothesis – Diet and Nutrition – COMMUNITY

A fascinating study tells us we’ve been thinking about excess body fat all wrong. Getting lean might be simpler than we ever thought.

Whether you’re very overweight or just a little too pudgy for your liking, the usual advice is “Stop!” Stop eating so damn much. Stop eating those particular foods. Stop consuming so many carbs. Stop snacking. Stop eating late at night. Stop eating your kid’s leftovers.

Stop, stop, stop!

But what if the answer all along – the cure for sedentary-person obesity and gym-guy chubbiness – was “Go!” Specifically, go eat some protein. That’s the gist of something called the protein leverage hypothesis.

I learned about this from Bill Campbell, Ph.D., and I’ll be paraphrasing him liberally here.

Protein appears to have leverage over your eating habits. Primarily, it’s protein that influences – or even controls – your intake of carbs and fats and, therefore, your overall caloric intake. In short, a low-protein diet triggers you to consume more carbs, fats, and total calories.

The protein leverage hypothesis says that your body “prefers and prioritizes” protein. If you don’t give it the protein it wants, various bodily mechanisms drive you to keep eating. Call it a protein threshold. If you don’t meet it, you stay hungry and have cravings – your body’s way of asking for protein.

Problem is, your big dumb body doesn’t use words; it only signals you to keep eating. Most people answer their body’s call for protein with more carbs and fats, usually of the junky, neon-orange, puffy-snack variety. The cycle continues, calories are overconsumed, and now you’re shopping in the ever-expanding plus-sized section of Target.

Recent studies show that gen pop’s protein intake has decreased over the last few decades. For whatever reason – cooking less, eating more convenience foods, or being afraid of meat – people are eating less protein… and getting fatter.

There are many factors contributing to our growing waistlines. Could “go eat some protein” be the one-sentence solution? Well, it certainly wouldn’t hurt since “go eat some gummy bears” hasn’t worked so well. It’s not an easy hypothesis to test in a lab, but researchers gave it a shot anyway.

Would you sign up for a study that provided all your meals and snacks but jailed you to a research facility for twelve total days? Me neither, but researchers found 22 lean, healthy people who agreed to do it.

The participants were divided into three groups and given three different meal plans:

Group One Diet: 10% protein, 60% carb, 30% fat
Group Two Diet: 15% protein, 55% carb, 30% fat
Group Three Diet: 25% protein, 45% carb, 30% fat

All the groups stayed in the lab for four days at a time, took a week off, and then came back to the lab twice more, each time in a different group.

This is where it gets clever. The participants were blinded: they didn’t know which group they were in. The provided meals and snacks were made to look and taste the same. Here’s an example of two of the actual meals, one photo for each diet group:

I can’t differentiate between the lower and higher-protein meals. Can you?

The human lab rats were told they could eat as much or as little food as they wanted, and snacks were available all day. Foods were weighed and everything was analyzed and controlled, Big Brother-style. The researchers knew exactly how many calories everyone consumed.

The 10% low-protein group consumed 260 more calories than the higher-protein groups each day. The 15% and 25% protein groups were about the same on average. If you buy into the protein leverage hypothesis, this tells us that the protein threshold to meet is at least 15% protein (as a percentage of total daily calories).

To put that into real-world numbers…

• The 10% protein group had about 66 grams of protein per day.
• The 15% group had 85 grams.
• The 25% group had 138 grams.

Body fat wasn’t tested since these dietary interventions lasted only four days each, but eating 260 more calories per day – triggered by low protein intake – equals 1820 extra calories per week and 7280 bonus calories per month. All things being equal, that’s enough to gain two pounds of body fat every month. (Yeah, that’s some overly simplified metabolic math, but you get the idea: the 10% group would get fatter over time.)

First, keep this in mind: many dieticians and government health agencies say that women only need 46 grams of protein per day, and men need 56, maybe a smidge more if they’re athletes. The low-protein group in the study above was eating 66 grams… and they still overate and set the stage for future fatness.

Yes, the official Google-answer recommends that you under-eat protein. WebMD tells you to under-eat protein. The government tells you to under-eat protein. That’s why everyone is so lean and disease-free! (That joke sponsored by Pfizer.) Either the “experts” are woefully behind the science or they’ve been compromised. I’ll let you decide as I adjust my flattering tinfoil hat.

That aside, it looks like everyone needs to get at least 15-25% of their daily calories from protein if they want to avoid fat gain. But that’s a minimal goal for lifters, athletes, and people who like to look great with their clothes off.

There are several smart protein-intake formulas, but the easiest to remember is to eat roughly a gram per pound of body weight, unless you’re obese. Don’t sweat if you fall a little short or go a little over. (If you are a high-calorie human, choose a healthy goal weight and eat that many grams of protein daily.)