As we all grow older, many of us may wonder how age affects our weight, body, skin, and metabolism. Most of us are already familiar with metabolism since it is linked to weight loss. You or someone you know has probably even blamed a slow metabolism for his or her weight gain. Instead of speculating, it’s best to get into the details of metabolism, and its relation to weight - and finally answer the question: Can we control our metabolism, as we get older to prevent weight gain?
Metabolism is how the body uses food as energy and then burns that energy to keep you fueled throughout the day. It is affected by three major factors:
Basal Metabolic Rate (BMR): The amount of energy (calories) needed to maintain homeostasis.
Food thermogenesis: The number of calories used up to digest and absorb food.
Activity level: The number of calories used to fuel the body during exercise.
Basal metabolic rate is largely determined by gender, age, height, and weight. The calories needed to maintain this metabolic rate accounts for 60% of total calories burned each day. Basal metabolic rate (or BMR) is naturally at its highest during childhood and adolescence. But as we grow into adulthood, it begins to level off which can lead to weight gain if the diet and exercise level is not adjusted properly.
Aging takes a toll on the thyroid gland, the body’s central control for metabolism, which can in return slow metabolism and increase your chances of weight gain. Starting around age 30, the body’s metabolism naturally begins to slow down, and it slows by about 5% every 10 years after age 40 (1). This is usually due to the fact that our bodies tend to lose muscle and gain fat as we age. Gender also plays a role in determining metabolic rate, as women naturally have slower metabolisms than men. Men tend to have more muscle mass, meaning they require more calories on average.
So, the age-old question now becomes: what can we all do to combat a slowing metabolism as we age? The answer begins with the following three suggestions:
Build Lean Muscle Mass: As your BMR accounts for so much of your total energy consumption, it is important to preserve or even increase your lean muscle mass through exercise, especially strength and resistance training. Aim to strength train 2-3 times per week since consistently building up muscle mass will burn those extra calories. Doing high-intensity cardio exercises along with this helps produce an “after-burn’ where you burns extra calories even after your workout (3). If you currently have a disability and need to practice low-impact activities, begin with exercises like chair yoga, walking up hill, Pilates, cycling or aqua aerobics.
Eat Well and Eat Often: In order to lose weight, you need to consume the right amount of calories for your body. The key is not to over eat or drastically under eat for your BMR. Eating too little can cause dips in blood glucose levels and glucose is the fuel to feed your brain. In order to gain lean muscle mass, you must eat enough nutrients for muscle growth. A good habit is to eat smaller meals with 100-200 calories snacks in between to keep blood-sugar levels balanced since they tend to fluctuate every three hours (3). Stick to a moderate calorie diet with plenty of protein-rich foods to promote muscle growth and strength. Some common sources of high-quality protein include: chicken, turkey, quinoa, beef, seafood, eggs, cottage cheese and tofu.
Don’t Skip the Sleep: Sleeping less than 7 to 8 hours a sleep per night may cause you to consume more calories the next day. According to a study in the American Journal of Clinical Nutrition, a single sleepless night reduces your resting metabolic rate by about five percent several hours into the next day (3). Simply put: more sleep equates to a higher metabolism so turn off that iPhone early at night and hit the sack for some quality rest.