I'm all about shattering diet myths.

For example, you may have already seen the news flash that snacking doesn't actually increase your metabolism, despite the fact that most “diet experts” tell you to graze on several small meals per day to keep that metabolic fire stoked.

Today, I've got another diet myth news flash for you: eating less does not cause fat loss.

Yes, you heard me right. You're about to find out why eating less does not cause fat loss – but first you should know that today's diet myth comes straight from Jonathan Bailor, author of a brand new book that I highly recommend you check out: “The Calorie Myth: How To Eat More, Exercise Less, Lose Weight and Live Better“.

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Why You're Losing Muscle, Not Fat.

Let's begin with a quote:

“The reduction of energy intake continues to be the basis of…weight reduction programs…[The results] are known to be poor and not long-lasting.”

– George Bray, Pennington Biomedical Research Center

Eating less does not create the need to burn body fat. Instead, it creates the need for the body to slow down. Contrary to popular opinion, the body hangs on to body fat. Instead, it burns muscle tissue, and that worsens the underlying cause of obesity. Only as a last resort, if the body has no other option, it may also burn a bit of body fat.

Why does the body hang on to body fat and burn muscle? To answer that question, let’s look at it another way.

What does our metabolism want more of when it thinks we are starving? Stored energy.

What is a great source of stored energy? Body fat.

So when our metabolism thinks we are starving, does it want to get rid of or hold on to body fat? It wants to hold on.

Next, what does our metabolism want less of when we are starving? It wants less tissue (which burns a lot of calories). What type of tissue burns a lot of calories? Muscle tissue. So when our metabolism thinks we are starving, it gets rid of calorie-hungry muscle tissue. Studies show that up to 70% of the weight lost while eating less comes from burning muscle—not body fat!

Burning all this muscle means that starving ourselves leads to more body fat—not less—over the long term. As soon as we stop starving ourselves, we have all the calories we used to have but need less of them, thanks to all that missing muscle and our slowed-down metabolism. Now our metabolism sees eating a normal amount as overeating and creates new body fat.

In the Journal of the American Medical Association, researcher G.L. Thorpe tells us that eating less does not make us lose weight, “…by selective reduction of adipose deposits [body fat], but by wasting of all body tissues…therefore, any success obtained must be maintained by chronic under-nourishment.” It is not practical or healthy to keep ourselves “chronically under-nourished,” so we don’t. Instead, we yo-yo diet. And that is why eating less is not an effective long-term fat loss approach.

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The Bad Side Effects Of Food Deprivation

Imagine watching TV and seeing a commercial for a new medication. The ad tells you the medication slightly improves your vision as long as you keep yourself chronically sleep-deprived. At the end of the commercial, a quieter voice lists the medication’s long-term side effects. One of them is that your vision will become much worse if you ever go back to sleeping a normal amount.

Would you ever use that medication? Of course not. You cannot go through life tired. Its temporary benefit is not worth its long-term side effects.

Now imagine another commercial.

This one is for a mail-order weight-loss meal program that slightly reduces your weight as long as you keep yourself chronically food-deprived. At the end of the commercial a quieter voice goes though the program’s side effects. The side effects include making you much heavier if you ever go back to eating a normal amount.

Would you ever use that program? Of course not. You cannot go through life hungry. To escape the superstition of starvation, let’s dive deeper into the science of its side effects.

My favorite experiment showing the side effects of eating less took place at the University of Geneva and involved three groups of rats all eating the same quality of food.

Normal Group: Adult rats eating normally.

Eat Less Group: Adult rats temporarily losing weight by eating less.

Skinny Group: Young rats who naturally weighted about as much as the adult Eat Less group immediately after this group ate less.

If the study were conducted on humans, the Normal Group would be typical thirty-five-year-old women. The Eat Less Group would be thirty-five-year-old women cutting calories until they fit into their high school jeans. And the Skinny Group would be high school girls who fit into size four jeans without trying.

For the first ten days of the study, the Eat Less Group ate 50% less than usual while the Normal Group ate normally. On the tenth day:

The Skinny Group showed up and ate normally.

The Eat Less Group stopped starving themselves and started eating normally.

The Normal Group kept eating normally.

This went on for twenty-five days and the study ended on day thirty-five.

At the end of the thirty-five day study, the Normal Group had eaten normally for thirty-five days. The Eat Less Group had eaten less for ten days and then normally for twenty-five days. And the Skinny Group had eaten normally for twenty-five days.

Which group do you think weighed the most and had the highest body fat percentage at the end? The Skinny Group seems like an easy “no” since they are younger and naturally thinner than the other rats. Traditional fat loss theory would say the Eat Less Group is an easy “no” as well since they ate 50% less for ten days. So the Normal Group weighed the most and had the highest body fat percentage at the end of the study, right?

Nope.

The Eat Less Group weighed the most and had the highest percent body fat. Even though they ate less for ten days, they were significantly heavier than those who ate normally all the way through. Eating less led the rats to gain—not lose—body fat.

MacLean at the University of Colorado describes this general metabolic behavior: “[When we eat less] metabolic adjustments occur…[which] contribute to a large potential energy imbalance that, when the forcible control of energy intake is relieved…results in an exceptionally high rate of weight regain.”



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Super Accumulation of Fat

Talk about side effects. Eating less was worse than doing nothing.

Why?

After our metabolism is starved, its number one priority is restoring all the body fat it lost and then protecting us from starving in the future. Guess how it does that? By storing additional body fat. Researchers call this “fat super accumulation.” From researcher E.A. Young at the University of Texas: “These and other studies…strongly suggest that fat super accumulation…after energy restriction is a major factor contributing to relapsing obesity, so often observed in humans.”

The most disturbing aspect of fat super accumulation is that it does not require us to eat a lot. All we have to do is go back to eating a normal amount. The Eat Less Group in the study gained a massive amount of body fat quickly while eating the same amount as the Normal Group and the Skinny Group. The metabolism was trying to make up for the past losses.

There is another reason: eating less slowed the metabolism. Put the same quantity and quality of food and exercise into a slowed-down fat metabolism system, and out comes more body fat.

The University of Geneva researchers discovered that the Eat Less Group’s metabolisms were burning body fat over 500% less efficiently and had slowed down by 15% by the end of the study. They remarked: “These investigations provide direct evidence for the existence of a specific metabolic component that contributes to an elevated efficiency of energy utilization during refeeding after low food consumption,” or once eating less stops.

Starvation does not make us thin. It makes us stocky, sick, and sad. It’s bad for health and it’s bad for fat loss. Your body just doesn’t work that way. Eating less does not cause fat loss.

Want more myths shattered from author Jonathan Bailor? Be sure to check out his new book “The Calorie Myth: How To Eat More, Exercise Less, Lose Weight and Live Better“. You may also want to tune into my podcast with Jonathan entitled “Can Some Foods Cripple Your Body’s Ability To Burn Fat?” – or you can check out the episode where I was a guest on Jonathan's podcast entitled “A Bit Of Biohacking“.

Questions, comments or feedback about how eating less does not cause fat loss? Leave your thoughts below!

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