Metabolism - The Science Behind Weight Loss

Posted by Dr. Niveditha Navin on 31st Aug 2023

Metabolism - The Science Behind Weight Loss

Have you met people who complain about eating less and gaining weight or someone who eats whatever they want, and apparently never gain weight due to fast metabolism? Well both scenarios raise the same question- What is the role of metabolism in weight gain or loss?

What is Metabolism?

Generally people think metabolism is only about a muscle or an organ, but it actually refers to all the processes occurring in each and every cell in your body. It is the process by which all your cells convert what you eat and drink into energy. More simply, it's the rate at which your body expends energy or burns calories to breathe, circulate blood, to grow and repair cells.

Metabolism runs 24/7, even while you are asleep or at rest so that your body functions efficiently; this is known as your basal metabolic rate (BMR). The body’s major organs- brain, liver, kidneys and heart account for about half of the energy burned at rest while digestive system and body muscles account for the rest.

Metabolism and weight

Metabolism varies a lot between people and is affected by multiple factors such as your genetics, your body composition that is the amount of lean muscle or fat tissue in the body, your age, lifestyle habits, physical activity and also sex, as women with any given body composition and age burn fewer calories than men.

Metabolism can also affect how energy is obtained from foods. For example, when we eat more than we need, the body uses the carbohydrates and protein from these foods as fuel, and stores the extra calories as fat – causing weight gain. Thus, weight gain and obesity are both linked to metabolic rate. So to lose weight, you need to burn more calories than you take in and for this you need to create an energy deficit by reducing portion sizes, limiting added sugars and saturated and trans fats. One must also keep in mind that as you age, you may need to eat fewer calories as the amount of muscle you have tends to decrease with age due to lesser activity, slowing down your metabolism.

So the question is, is it possible to speed up a naturally slow metabolism, or rev up one that has become sluggish over time? It is often a small change such as adopting a healthier diet and making sure you get enough exercise, may help you burn more calories. Here are a few tips to help you boost your metabolism:-

  1. Fuel up with water- Your body needs water to process calories. If you are even mildly dehydrated, your metabolism may slow down. Drinking more water benefits weight loss and increases the amount of calories you burn.
  2. Muscle building exercise- Exercise is a key component of weight loss because when you build lean muscle mass, your body has to use more energy to maintain it and muscle tissue tends to burn more calories at rest compared to fat tissues. So high intensity training, muscle building exercises and aerobic exercises, could be a gamechanger!
  3. Eat Smart- Having a small meal at regular intervals of every 3-4 hours can crank up your metabolism, so you burn more calories over the course of a day.
  4. Food choices- intake of proteins such as tofu, eggs, white meat chicken, nuts, beans, fish help burn more calories compared to carbohydrates and fats. Adding chilli peppers or cayenne pepper to your meal can boost your metabolic rate as capsaicin, a chemical found in them, helps boost your metabolism. Replacing cooking fats with coconut oil may also have modest benefits for weight loss due to its unique fatty acid profile that increased metabolism by 12%. Green tea can also increase your metabolism by 4–5%.
  5. Stand up often- Sitting too much is bad for your health because long periods of sitting burns fewer calories and can lead to weight gain.
  6. Get a goodnight sleep- sleep deprivation has been linked to obesity. It's been shown to boost the hunger hormone ghrelin and decrease the fullness hormone leptin.This could explain why many people who are sleep-deprived feel hungry and struggle to lose weight.
  7. Supplements- vitamin D and B, calcium, iron, NMN supplements have shown to improve our metabolic health. Studies have shown that NMN enhanced energy metabolism and suppressed age associated weight gain. Moreover, in a study where Vitamin D - deficient women got their blood levels of vitamin D raised to recommended levels they lost more weight.

So, when it comes to weight, metabolism is important and following a few tips stated above can clearly change how you balance the calories you take against the calories you burn, which can help you achieve an ideal body weight.

About the Author

Dr. Niveditha Navin

Dr. Navin is a clinical research specialist, who holds a degree in dentistry. After completing her postgraduate diploma in clinical research, she has experience working as a clinical affairs specialist in the pharmaceutical industry. She is passionate about medicine and wishes to carve a distinct niche in the field of research.


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