Home » 5 Reasons Metabolism Slows Down & Tips to Improve It

5 Reasons Metabolism Slows Down & Tips to Improve It

Your digestion is sluggish and you feel tired, cold, and you’ve gained weight even though you haven’t been eating more than normal.  You are convinced that your metabolism is slow. You may be right. But why does this happen?  Here are reasons your metabolism slows down?

Reasons Metabolism Slows Down | Hacks to Speed Up Metabolism

Why Metabolism Slows Down?

Metabolism includes all of the biochemical reactions in your body that use nutrients and oxygen to create energy.  And there are lots of factors that affect how quickly (or slowly) it works, i.e. your “metabolic rate” (which is measured in calories).

But don’t worry – we know that metabolic rate is much more complicated than the old adage “calories in calories out”!  In fact, it’s so complicated I’m only going to list a few of the common things that can slow it down.

Examples of common reasons why metabolic rates can slow down:

  • low thyroid hormone
  • your history of dieting
  • your size and body composition
  • your activity level
  • lack of sleep

We’ll briefly touch on each one below and I promise to give you better advice than just to “eat less and exercise more”.

Low Thyroid Hormones

Your thyroid is the master controller of your metabolism.  When it produces fewer hormones your metabolism slows down.  The thyroid hormones (T3 & T4) tell the cells in your body when to use more energy and become more metabolically active.   Ideally, it should work to keep your metabolism just right.  But there are several things that can affect it and throw it off course.  Things like autoimmune diseases and mineral deficiencies (e.g. iodine or selenium) for example.

Tip: Talk to your physician about having your thyroid hormones tested. Don’t just get a TSH number but a complete thyroid panel to really understand what is going on.

Reasons Metabolism Slows Down | Hacks to Speed Up Metabolism | Dieting

Your History of Dieting

When people lose weight their metabolic rate often slows down.  This is because the body senses that food may be scarce and adapts by trying to continue with all the necessary life functions and do it all with less food.

While dieting can lead to a reduction in the amount of fat, it, unfortunately, can lead to a reduction in the amount of muscle you have.  As you know more muscle means faster resting metabolic rate.

Tip: Make sure you’re eating enough food to fuel your body without overdoing it. Avoid low-calorie diets which can wreak havoc in your organs, hormones and even thyroid glands.

Your Size and Body Composition

In general, larger people have faster metabolic rates.  This is because it takes more energy to fuel a larger body than a smaller one. However, you already know that gaining weight is rarely the best strategy for increasing your metabolism.

Muscles that actively move and do work need energy.  Even muscles at rest burn more calories than fat.  This means that the amount of energy your body uses depends partly on the amount of lean muscle mass you have.

Tip: Do some weight training to help increase your muscle mass. Body exercises such as pushups, squats, and crunches all can help with muscle mass as well.

Reasons Metabolism Slows Down | Hacks to Speed Up Metabolism | Pushups

Which leads us to…

Your Activity Level

Aerobic exercise temporarily increases your metabolic rate.  Your muscles are burning fuel to move and do “work” and you can tell because as you move you feel hotter. High-intensity interval training can improve your metabolic rate in a short period of time while increasing your muscle mass.

Even little things can add up.  Walking a bit farther than you usually do, using a standing desk instead of sitting all day, or taking the stairs instead of the elevator can all contribute to more activity in your day.

Tip:  Incorporate movement into your day, but prioritize regular exercise.

Lack of Sleep

Research shows the influence that sleep has on your metabolic rate.  The general consensus is to get 7-8.5 hours of sleep every night.

Tip: Try to create a routine that allows at least 7 hours of sleep every night.

Tip: Selenium is a nutrient that can help your thyroid as well as your sleep.  The recipe below is rich in selenium and may help you when your metabolism slows down.

Recipe: Chocolate Chia Seed Pudding

Serves 4

  • ½ cup Brazil nuts
  • 2 cups water
  • nut bag or several layers of cheesecloth (optional)
  • ½ cup chia seeds
  • ¼ cup unsweetened cacao powder
  • ½ teaspoon ground cinnamon
  • ¼ teaspoon sea salt
  • 1 tablespoon maple syrup

Blend Brazil nuts in water in a high-speed blender until you get smooth, creamy milk.  If desired, strain it through a nut bag or several layers of cheesecloth.

Add Brazil nut milk and other ingredients into a bowl and whisk until combined.  Let sit several minutes (or overnight) until desired thickness is reached.

Serve & Enjoy!

Tip:  Makes a simple, delicious breakfast or dessert topped with berries.

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Reasons Metabolism Slows Down | Hacks to Speed Up Metabolism
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  1. Mistle says:

    This is really great information! Sleep is so important when it comes to keeping your metabolism going. I find when I get more sleep the more energized I am.

  2. Dawn says:

    These are all spot on! I am hypothyroid and let me tell you how big a difference being on medication makes. I was always struggling with fatigue and weight fluctuations, and things are 1 million times better. Sleep is huge too!

    • Karen says:

      I am sorry to hear you having a hypothyroid. Keep doing these things, they will help with your symptoms. Hang in there, take care of yourself and you can live a fabulous life feeling your best that you can.

    • Karen says:

      I am sorry to hear you have an underactive thyroid. Keep doing these things, they will help you feel your best and help support your thyroid. You can feel great when you take care of yourself.

    • Karen says:

      Yes, a good night’s sleep makes a difference in all areas of your life. You eat less, move more, have quicker reactions, feel overall better. Hope you get a good sleep tonight.

  3. GiGi Eats says:

    I have been getting really really into weights lately. I work out every day and have for a very long time, but never really got into the weight room – but that’s changing 🙂

  4. Patrick says:

    The main reason why I dread winter,even when I am outside working,I never seem to be moving as much as during the warmer months and I can sense getting heavier because of lack of movement. I don’t sleep the best either….

    • Karen says:

      All true, but our bodies are made to store fat during the winter, not know when they will need it for heat and energy. So definitely feels like we are heavier. Work on your sleep but going to bed at the same time and getting up at the same time every day.

  5. Chrissy says:

    These are some really good tips! I noticed that my metabolism has gotten lower over the years, and I’ve been wanting to improve on it for a while. Thanks once again! x

  6. Ilka says:

    Love all the valuable info in this post! Brazil nuts are a great source of selenium and I have recently started incorporating them into my diet again.

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