I am at that age (early 40s) where I have many family members and friends trying to lose weight. It’s definitely tough for us to stay slim as we age. One of the main reasons is that we have been steadily losing precious muscle since our early 30s. It’s called sarcopenia. On average, physically inactive people lose 3-5% of their muscle mass per decade, my 6th edition NASM textbook states 5% per decade. That might not seem like a big deal, but it is. Your amount of muscle mass pretty much dictates your BMR.
Your BMR (basal metabolic rate) is the amount of energy expended while at rest. Your muscles burn more calories in order to function, meaning the more muscle mass you have the more energy (calories) your body burns. Pretty cool, eh?
So as we age, it’s important that we exercise. Walking and light aerobics are great for our cardiovascular health (which lengthens our life expectancy), plus it will burn a little extra calories. However, it’s only when we add strength exercises that work our muscles that builds muscle on our bones. Strength training is what changes our body composition— the ratio of lean mass vs our fat mass on our bodies.
Another important factor is our TDEE (total daily energy expenditure).
Your TDEE is the overall number of calories your body uses on a daily basis, and it’s based on your BMR plus your activity level throughout the day. So gardening, taking the stairs instead of the escalator, walking the dog, parking the car farther than usual, and intentional exercise (like going for a run, strength training, HITT class) helps increase your TDEE.
Then there are our food choices. While it’s true that a calorie is a calorie, it’s not that simple. The thermic effect of food (TEF) is the amount of energy expended above BMR as a result of the processing of food (digestion) for storage and use. Protein uses more energy (calories) to digest than the other macronutrients (carbohydrates, fat, alcohol). And while fat doesn’t use the same amount of energy to digest, it doesn’t spike insulin levels, which studies show is an important factor to the weight debate.
Insulin is a hormone that is secreted from your pancreas in response to two macromolecules: glucose (from carbohydrates) and protein. Insulin takes sugar from the bloodstream and helps it enter the cells to be used for energy or to be stored. It also stops glucose from being released by the liver into the bloodstream.
The rate at which ingested carbohydrate raise blood sugar and its accompanying effect on insulin release is referred to as the glycemic index (GI). Carbohydrates are not all equal, they come in different forms: simple sugars (honey, table sugar), starches (oats, whole grains, yams with skin), and cellulose (fibre from the skins of fruits and veggies). When your body consumes too many high glycemic carbohydrates (note: this can also happen when you consume too many calories too many times), insulin spikes trying to stop the influx of sugar in the blood and so puts glucose (energy) into all cells, including your fat cells. This means that if you eat a meal that is high in simple sugars (processed food) your body pumps out insulin in response to hold onto the energy and store it for later. We don’t want that energy stored in our fat cells (making them bigger!) and we definitely don’t want it stored abundantly on our tummy, hips, and thighs!
I was recently listening to a great talk with Gary Taubes and Dr. Mark Hyman. Taubes is the author of The Case Against Sugar. He says that we weren’t designed to eat the amount of sugar we typically consume. His theory is that the overconsumption of sugar is why over the past 100 years people have been getting fatter. It has something to do with the insulin production in our bodies, making it hard for us to lose weight even though we are watching what we eat. About 1 in 3 people in the USA are prediabetic. Taubes highlighted an interesting observation I didn’t connect before: type 1 diabetics (people who don’t produce insulin at all) are very thin even though they eat a lot of food, even 10,000 calories or more, because it’s the insulin production that stores the energy into our fat cells, of which they don’t have any. Type 2 diabetics (those who over the years produced too much insulin and their bodies have become resistant to it) are overweight and have a difficult time losing weight, no matter what they do. He explains that many of us, perhaps even 50%, are genetically unable to eat the amount of sugar we do, which would explain our weight loss troubles.
This is a very complex topic, I have tried to just touch upon the main takeaways. And really what I have presented here only touches the surface of the findings from new research, as health professionals try to figure out what is causing so many people to struggle with their extra weight. But I think we are getting close, which is exciting, and more studies on the effects of insulin may be the key.
Here are some simple things to try:
Strength train 2-3 times a week to build muscle mass. Start with bodyweight exercises first, and then when it starts to feel easy add hand weights to your program. Even better: join a gym and use heavier weights and machines. If you are a woman, please don’t worry about “bulking” up, I try to lift heavy (for example I shoulder press 20lbs for 12 reps) and I find I get thinner, not bulkier.
Cut out processed sugar from your diet. This one is tough, I know! However, eliminating all added sugar will help your weight loss goals abundantly. One of my daughters struggles with insulin resistance, which is the precursor to prediabetes. We cut out sugar last year, and she naturally lost weight and gained more energy, but we think she will always need to watch her sugar intake to stay healthy.
Eat more protein (on average: 1 gram per 1 pound of body weight). This helps keep the muscle you already have, as well as adding more if you begin to strength train. David Heber MD, PhD gives an amazing talk on Doctor’s Farmacy about our need of protein. Note: you cannot gain more muscle if you don’t strength train.
Fill up on veggies. Having 50% veggies on your plate for lunch and dinner helps with a feeling of satiety and adds much needed fiber and micronutrients (vitamins).
Have a small, no/low sugar treat every day. This may seem counterintuitive when dieting but having just a little yummy goodie keeps the cravings at bay. If I don’t have my four squares of dark chocolate a day, I will cheat BIG time later on.
And lastly, this is one I suggest all the time: log your food intake. Doing this gives you an idea on what you are eating and how much. Calculate your Total Daily Energy Expenditure (TDEE).
Step 1: weight (lbs) x 10 = BMR
Step 2: BMR x activity factor = TEE . Daily activity factor: very light 1.2 (desk job, not exercising), low active 1.5-1.6 (desk job, light exercise), active 1.6-1.7 (desk job, exercises most days of the week), heavy 1.9-2.1 (physical labour, athlete, vigorous exercise). Example: I weigh 128lbs. 128×10= 1280 calories is my BMR. 1280×1.6= 2048 calories. Which is exactly how many calories I consume daily to maintain my current weight.