Losing Fat

by | Losing Body Fat

losing fat

Well, it’s that time of year where many of us start thinking about trying to get into better shape, and losing fat. But, where do you start? How does it work? Are the latest fad diets any good or should you try a weight loss drug?

Ideally, you’d like an approach that’s sustainable, otherwise, you’ll simply gain it all back, and then some. In Nutrition Fundamentals it was stated that the 2 biggest factors in changing your body composition are the number of calories you consume at 50%, followed closely by the macro nutrient distribution at 30%. Meal timing comes in at 10%, followed by micronutrients and supplements at 5% each.

From this we can see that the most bang for your buck comes from controlling your calories and macro nutrient choices. Weight loss drugs help you reduce the number calories you consume by making you less hungry. But, as soon as you stop the drugs your appetite comes back, along with those pesky added calories, and eventually the body fat comes back.

Today we’ll discuss how diet and exercise affect your success in losing fat.

Diet and Energy Expenditure

The mechanisms involved in losing fat are well understood. While there are generally 2 ways to approach it in a sustainable way, the best approach is to combine them.

The first approach of losing fat would be to run a calorie deficit with diet, while the second would be to increase activity level to create a calorie deficit. In either case, it’s advantageous to minimize losing muscle in the process because losing muscle is counterproductive.

Basically, in order to lose a lb of fat, we have to burn 3,500 calories more than we consume. By the way, 3,500 is a lot of calories, more than most people burn in an entire day.

Let’s suppose we want to lose a pound of fat a week. Our total daily energy expenditure (TDEE), comprised of the following, needs to be 500 calories more than we consume:

  • Basal Metabolic Rate (BMR) or Resting Metabolic Rate (RMR). These are the calories your body burns 24/7 just being alive. It includes powering your brain, heart, lungs and other organs, and your skeletal muscle mass (SMM). The only one of those you can increase is SMM. The more muscle you have the more calories you burn.
  • Non-Exercise Activity (NEAT). Things like cleaning the house, taking care of the yard, laundry, grocery shopping, etc.. The more active you are, the more you burn.
  • Exercise Activity (EAT). Structured exercise like cardio and weightlifting. This is far superior to NEAT.
  • Thermic Effect of Food (TEF). Food requires energy to digest, some more than others. For example our bodies readily absorb sugars and fat. On the other hand, our bodies have to work to process protein.

Losing fat through diet

Start by figuring out your maintenance calories. You can use a tool like this: https://www.calculator.net/calorie-calculator.html

Now decide how much fat you want to lose per week. The tool above will compute how many calories you should eat to lose fat at a given rate. It works by computing how much of a daily calorie deficit you need to lose your weekly target.

I wouldn’t advise losing more than a pound a week through diet alone. To lose a pound a week w/o exercise you will need to run a 500 calorie deficit a day (500 x 7 = 3500).

Not everyone should try to run this big of a deficit. If your maintenance calories are below 2,000 calories a day, you’d be better off running a 250 calorie deficit through diet. The lower your maintenance calories, the lower your deficit should be to remain healthy and avoid losing muscle.

Losing fat through increased energy expenditure

Then comes other things you can do to add to your fat burning. Increasing your TDEE. That’s where NEAT, EAT, and TEF come in.

NEAT – Non-Exercise Activity

To increase NEAT, get up. Move around. Clean the house. Do some gardening. Go grocery shopping. Wash the car. The more sedentary you are, the less NEAT calories you burn.

EAT – Exercise Activity (Structured)

Which brings us to EAT. If you want to use exercise to increase your calorie deficit it requires discipline and consistency. Mild cardio is probably the best way to add extra calorie burn, but it must be done regularly. The idea here is to find something you can sustain for weeks or months at a time.

I have found I can burn about 100 calories every 15 minutes by walking. That’s 700 calories a week if you do it every day. If you do 30 minutes it’s 1400 calories, and so on. If you can walk 8,000 – 10,000 steps a day, you can lose a pound of fat a week just walking.

Now, walking is low intensity and as a result it almost exclusively burns fat. As you transition to higher intensity exercise your body shifts to using glucose, which still burns calories, but not exclusively fat.

Weightlifting is also a good choice because it is muscle sparing, and in some cases you can even build muscle while losing fat. While weightlifting does burn calories, the real benefit is in protecting and/or building new muscle mass. To get this benefit you need to lift at least 2-3 days a week.

TEF – Thermic Effect of Food

To increase TEF eat a high protein diet, and eat complex carbs instead of simple carbs. Protein is more important when you are restricting calories because it’s muscle sparing. Protein becomes even more important as we age because our bodies naturally become less efficient at absorbing protein.

The guidance is 0.8 grams of protein per pound if you aren’t doing structured exercise or when you run a calorie deficit. 1-1.2 grams per lb. if you are lifting weights and running a calorie deficit. You will have to play with your macros to make the numbers add up to your calorie target.

Avoid alcohol. Burning fat requires your liver to do its part. When you drink your liver prioritizes processing alcohol (as opposed to fat), because alcohol is a toxin. Alcohol is also empty calories, meaning there is no nutritional benefit. As a result, alcohol consumption inhibits your ability to burn fat, or worse, causes you to accumulate more fat.

Alcohol is also calorie dense. In the best case you’d limit to clear alcohol like vodka or tequila, but even these are 80 calories a shot. Most people mix with something sweetened, so add those calories in too. Beer and wine, and other liqueur go up from there.  Basically, every drink is at least 30 minutes of walking to work off.

Maintaining target body fat %

Once you hit your target body fat % you can recompute your maintenance calorie number (it will go down as you lose weight), and maintain your new body fat level. You can also increase your calories slightly to encourage muscle growth, assuming you are weight training, while being careful not to increase your body fat.