How Weight Loss Really Works

How Weight Loss Really Works

How Weight Loss Really Works

For many of us, weight loss is perhaps one of the most mysterious, frustrating processes that we experience (or don’t experience). It can be incredibly confusing – there’s a lot of conflicting information out there, and on top of that, our natural drive as humans is to conserve fat, not to burn it. But in our 21st-century first-world wonderland of abundance and variety, our wiring works against us, and most of us get stuck at a higher weight than is really good for us.

What really happens when you lose weight, and how can you ensure that you’re doing it in a healthy, sustainable way?

Let’s start with the metabolism.

The Science

The metabolism is simply the amount of energy that your body expends to maintain itself. Metabolism runs on “calories in” (what you eat) and “calories out” (what you “burn” through activity).

The first two major factors that influence your metabolism are:

  • Your weight is the most powerful base predictor of your metabolism. We often think of the metabolism as a magical calorie-burning process for weight loss, because that’s the context in which we hear about it most often. But let’s re-frame your thinking: your metabolism, rather than being a vehicle for weight loss, is a mechanism of weight maintenance. Your metabolism the energy that your body expends to maintain itself, weight included. The more you relatively weigh, the “faster” your metabolism will be, because you literally have more body to maintain. The 150-lb version of you has a faster metabolism than the 130-lb version of you, for example. This means that your metabolism burns calories all day long, even through the night as you sleep. Your body requires energy just to keep your heart beating and your lungs pumping and your brain humming – more than a thousand calories of energy every day, in fact. Obviously this is far more than you burn through exercise.
  • Next, your level of daily activity, not including exercise, is the biggest variable that you can control to increase your daily caloric expenditure. This includes activities like climbing stairs, walking around, cleaning your house, putting away groceries, etc. If you compare burning 300 calories on the treadmill to burning 400-800 calories by going about your daily business, you can see how much your overall level of activity has an impact on your metabolism. Again, this is far more than we burn through exercise. This is why I encourage my clients to wear step trackers and become aware of their daily level of activity – not only do we underestimate the caloric impact of keeping physically busy, but we also underestimate how sedentary we actually are.

These two factors – your starting weight and your level of daily activity – are the basis on which the next variables are built. The next two factors that you can control are:

  • What you eat each day is the “calories in” part of the equation, and is – technically – “easier” to manage than “calories out.” For example, if one donut is 300 calories and a run burns 300 calories, you can see how skipping the donut is far easier than running 3 miles (but is it “easy”? More on that later!). It is essential for weight maintenance or weight loss that your daily caloric intake is equal to or less than your daily caloric output. This is why people often say that a “six-pack is made in the kitchen.” Mastering good nutrition habits returns rich dividends for a long-term healthy weight, six-pack or not, because anytime you are in a caloric deficit, your body will deplete the energy storage in your fat cells to use for fuel. This results in weight loss.
  • Finally, how you exercise is the most overt “calories out” part of the equation, and it’s the one that gets the most attention (and for most people, the most significant financial investment). While I don’t want you to forget that your daily activity – walking around, climbing stairs, putting away groceries, etc. – cumulatively burns more calories than exercise, formal exercise (especially strength training) in the right dosage is also vitally important because of non-caloric benefits like improved hormone balance, happier moods, the promotion of muscle development, increased strength, pain reduction, and a generally better quality of life, just to name a few. Also, a consistent exercise habit may not burn the calories needed to elicit weight loss, but a lot of research shows that the same consistent exercise habit helps with weight maintenance once you’ve lost weight.

To sum up, our metabolic balance (and thus weight loss) is controlled by: 

  • Our weight, which results in our resting metabolic rate
  • Our daily level of activity
  • How much we eat
  • How much (and how) we exercise

If you only take those four factors into account, weight loss should be simple.

That’s the hard science. That’s the way it should work.

Now – enter the human brain and human behavior – let’s talk about why what should work doesn’t always work…

…And for some people, never seems to work.


Technically, weight loss is a “calories in, calories out” endeavor. It should work that way, at least. If you simply reduce your eating by about 300-500 calories per day for a month and wear a step tracker to make sure you are getting in about 10,000 steps a day, you should lose weight steadily.

However, I’m sure many people reading this have had the opposite experience. Sometimes, it seems that the harder you work to lose weight, the harder it is to budge. 

The more you focus on eating healthfully, the more tempting “off limits” foods seem. The more you exercise, the hungrier you get and the more you eat. Then, the moment you “fall off the wagon,” you’re off for good.

This is where I want to return to the idea of metabolism as a vehicle for weight maintenance, not weight loss. Your body is happiest when it is in equilibrium.

Your body has a sort of thermostat in your brain that dictates the level of body fat that you “should” carry. This thermostat is adjustable, but a hard-line approach to calorie restriction doesn’t necessarily adjust the thermostat. You may eat less and exercise more and initially lose weight, but if you don’t adjust the thermostat, your brain will gradually drive you to unconsciously move less and mindlessly eat more, because your thermostat is still set at a heavier weight. Eventually you will return to your original weight (or heavier).

This is one of the most frustrating experiences that my clients go through!

The secret is that it is essential not just to eat less and move more to lose weight, but also to take the actions necessary to adjust the thermostat at the same time.

But how do we adjust the thermostat?

Enter: palatability.


It’s a topic that I’ve been obsessed with this year – what foods elicit overeating, and how we can change our relationships with those foods.

The basic recipe for palatability is salt + sugar* + fat. When we eat foods that contain salt, sugar, and fat, overeating is almost inevitable, because there is a double whammy – not only are these foods typically high in calories for a small amount of volume (and a small amount of satisfaction), but they also turn up our fat storage thermostat in the long run.

*Keep in mind that sugar doesn’t just mean “refined table sugar,” but also processed, refined carbohydrates like white flour.

Examples of extremely palatable (but low satisfaction) foods include obvious culprits like donuts, but can also include the following foods that often make it onto health-conscious menus:

  • Meats with sauces
  • Sushi or poke with sweet sauces
  • Sweet potato fries
  • Salads with dressing
  • Chocolate with sea salt
  • Coconut or almond milk desserts or coffees
  • Nuts with any kind of special roasting or coating

With traditionally “healthy” foods, the palatability element is introduced by human engineering. Chicken breast, on its own, is extremely satisfying and difficult to overeat. But if you salt it and swim it in a glaze containing oil and sugar (even honey), you will find it very difficult not to overeat. Potatoes, again, are extremely satisfying. If you eat one potato, it is unlikely that you will eat more. But if you fry it in oil and salt, you will find it difficult to stop after a potato’s worth of fries. Raw, unsalted almonds taste fine but are not really “mind-blowing.” But process them with roasting, salt, and oil – and maybe even honey-roast them – and the whole container could be gone in less than an hour.

It’s why we have difficulty not overeating chocolate, cake, pizza, pasta, and other delicious “sinful” foods. But we also have to be aware of foods with buzzword-y “healthy” presentation, which are simply the same calorie-rich items with better marketing. Anytime you consume that magic combination of salt, fat, and sugar, it doesn’t matter whether the item came in a greasy MacDonalds bag or a fair trade, organic craft paper wrapper – it’s going to drive up your thermostat for overeating. 

How to Turn Down the Thermostat

This is why I said skipping the donut is technically easier than running for 30 minutes, but it may not actually be easier. If you take all factors into account, the reality is that:

  • We overall are more sedentary than we think
  • Formal exercise does not burn as many calories as we think
  • Most importantly, we eat more than we realize, because our food culture is over-saturated with hyperpalatable foods that trigger overeating and keep our fat storage thermostat elevated 

This is why weight loss is so hard for so many people.

It is also why, in my coaching groups, we discuss ways to re-wire our thinking, habits, and approach to healthy living. I don’t do “weight loss challenges,” because anyone can under-eat for 30 days to win a prize, and I don’t support that. When it comes to the kind of long-term success that frees people from chronic disease, it’s not just about “calories in, calories out.”

If you struggle with weight loss and want to permanently alter the way your body handles calories, these are the first three things you should do right away:

Start paying attention to the fat-sugar-salt combination and attempt to eliminate or severely limit your intake of foods like this. 

This will not happen overnight, because it is a learning process. But these three strategies will help enormously:

  • Cook 90% of the food that you eat. If your meals are coming from home, you have a huge degree of control over the ingredients.
  • Avoid most packaged foods. Obviously this does not include foods like raw, unsalted almonds, but I would even be careful of “health foods” like most granola bas or power bars.
  • When you eat out, request items without glazes or sauces. Does this seem a little over-the-top? Maybe. But I think it’s less aggressive (and more effective) than measuring/weighing all of your food, because it strikes overeating at its core – palatability.

If you are not sure about an item’s ingredients, ask yourself: do I have trouble overeating this food? If the answer is yes, it probably fits into this category.

Clean out your kitchen, refrigerator, and pantry to avoid willpower fatigue. 

You are not a “weak” person – it is human nature to desire and seek out food. If you have foods highly available in your home that you do not want to overeat, you are setting yourself up for failure. One of my clients pointed out that after she cleaned out her kitchen as part of my online group coaching, her cravings now pass in less than 30 minutes.

This is especially true with Christmas around the corner. I tell my clients, one day of overeating will not re-wire you. A month of overeating, however, definitely will. Check out (and share!) my blog post about holidays vs. holimonths. Eating the pecan pie at Christmas dinner won’t take your goals, but keeping one of those huge tins of caramel popcorn at your house (“for the kids”) is a terrible idea if you are working on re-wiring your approach to eating.

Develop an easy, sustainable exercise habit. 

Some people love going to the gym and pumping iron. Other people love going for a five mile run several times a week.

Most of my clients, though, do not inherently love exercise. For people who fit into this category – want to exercise but have trouble sticking with it – I recommend developing a habit like walking, because it is approachable, easy, and won’t leave you sore for days.

When I initially lost 50 pounds, my main form of exercise was walking. Even now, I am not a fan of highly-intense exercise, and I think it is an unfortunate fallacy that has developed in our fitness culture that in order for exercise to be effective, you must be “dead” after the session or sore for days after. For most people, I firmly believe that consistent exercise that is both moderately intense and moderately enjoyable is the long-term path to success.

To sum up:

  • Ditch hyperpalatable foods except on infrequent special occasions
  • Go easy on your willpower every single day by setting yourself up for success
  • Do easy exercise so that you’ll do it more often

No “go hard or go home.”

No “pain is weakness leaving the body.”

No complicated diets where you must totally eliminate food groups or fast for hours at a time.

By combining these three simple and fairly easy strategies, you empower yourself to stop fighting against your metabolism, and to instead turn down your thermostat so that weight loss can be happily maintained.

Interested in getting 24/7 support for 30 days as you take the first steps to re-wiring your brain? Check out my online group coaching option for a cost-effective way to get the help you need!