diets don't work

Why diets fail…

Diets don’t work. Ever. Period.

The research is conclusive; not only do diets NOT result in lasting weight loss, the majority of people who diet gain back their weight and MORE.

Why is this?

As always, I look to biology and evolutionary science for the answer…

Your body doesn’t like to relinquish body fat. We adapted to favor fat storage as a survival advantage.

Remember, we evolved over millions of years in an environment of scarcity and eked out an existence only by hunting and foraging every single day for enough calories to survive. But we were always on the edge of calorie-balance, meaning we basically covered our energy needs but rarely, if ever, had enough calories available to us to store body fat.

So, when we did, it was a GOOD THING! Stored body fat helped us to survive lean times!

Dieting, which basically means “significant calorie restriction,” doesn’t work because it triggers ancient biological warning signals in your body that famine is upon us. After all, no animal in nature will voluntarily starve itself in the presence of adequate calories.

So, sharply reducing calorie intake, especially over an extended period of time, must simply mean that adequate food isn’t available to us, and that’s a problem.

In response to the decrease in energy intake, your body brilliantly adjusts to the circumstances:

Daniel Lieberman, Professor of Human Evolutionary Biology, Harvard University

Think of it this way….

Let’s say your local electricity provider sends a message to it’s customers that energy stores are in short supply and in order to avoid running out, you need to reduce your usage.

What would you do?

I’ll tell you what I would do; I’d turn the lights off, stop running appliances unless absolutely necessary, unplug everything not critically important and scale down my electricity usage so that we don’t run out!

I’m hoping, if you live in my neighborhood, you’d do the same thing!

That’s the same situation as if:

Your local energy provider (YOU) sent out a message to it’s customers (ALSO YOU) that energy stores (CALORIES) are in short supply (FAMINE) and in order to avoid running out (STARVATION), you need to reduce your usage (LOWER YOUR METABOLISM).

When faced with calorie restriction your body responds by lowering it’s metabolism and becoming more energy efficient. This cancels out your calorie restriction.

Even worse, research shows that your metabolism may remain lowered for years after you’ve returned to your pre-diet eating habits! You’ll put on more weight, more quickly, eating the same amount of food you ate before your diet!

So, inadequate calorie consumption signals a threat to survival, potential starvation, and your biology is too smart for that. It adapted over millions of years for just this kind of situation.

You won’t be able to outsmart your biology that way.

So, if “calorie restriction” doesn’t work, what does?

What works for producing long-term fat loss is a multi-pronged approach:


1. It’s not just about calories in versus calories out. It’s about QUALITY of calories.

2. Reduce or eliminate processed foods and refined sugar. Our bodies are not biologically adapted to cope with high doses of simple carbohydrate and refined sugar and they are the number one cause of stored body fat, visceral (abdominal) fat, overweight, obesity, Type 2 diabetes and metabolic syndrome.

4. Make sure you get help on figuring out what your daily energy needs are and set up a nutrition program that provides it.

5. It’s more complex than this but if you make these changes you’ll improve greatly.

Physical Activity

1. Move. A lot. Your body needs consistent physical activity. We adapted to hours of daily physical activity and the biological effects of it are unmatched. Don’t think “exercise” or “working out,” think MOVEMENT. That means walking, jogging, climbing, hiking, rowing, playing tennis, gardening, surfing, etc. in addition to training at the gym.

2. Don’t think of physical activity in terms of “burning calories.” Throw that out. Think of daily physical activity as a full-body vitamin. It triggers biological processes that burn visceral fat, help regulate blood glucose levels, help to lower cholesterol and blood pressure, trigger anti-inflammatory cytokines, extend and expand your vascular system, improve cognition, ward off depression and a bunch of other things.

3. Physical activity is the single best thing you can do for your body. It is the number one factor in longevity.

1. Get 8 hours of sleep per night. Period. If you’re one of those people who say, “oh, I can get by on 5 hours of sleep!” you are wrong. You may have adapted to the sensation of sleep-deprivation but your body is suffering serious biological consequences.

2. Sleep deprivation correlates to weight gain, cognitive decline, increased appetite, poor blood sugar regulation, increased cortisol and a bunch of other stuff.

Stress Management

1. Chronic stress generally means (among other things) increased cortisol, hunger and stored body fat.

2. Turn off your phone whenever you can. Unplug. I’m not aware of a single scientific study that shows that’s it’s beneficial to check your email 80 times a day and perpetually be staring at a device that removes you from the real world and from actual human contact.

3. Spend quality time with family and friends. Humans are social animals (even introverts like me). Social contact has been show to improve health, life satisfaction and longevity. There are no studies that show social isolation to be beneficial.
4. Meditate/pray/relax, whatever your thing is, do it. It works. Even just 3 to 5 minutes a day.

Here’s the basic message here: Diets. Do. Not. Work.The science is clear but do we really need to look that far? If diets worked, everyone who had ever done one would be lean and healthy.

Instead, rates of disease related to obesity and overweight continue to grow.

The math is easy on this one.

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Jonathan Aluzas is co-owner of Arena Fitness, a fitness center that offers group training in Encino as well as personal training in Northridge.