Why is My Metabolism so Slow?

by Debbie Wright in Blog Posts, Body Type, Healthy Habits, Metabolism, Protein, Sleep, Walking, Weight Loss

September 10, 2017

If you’ve gained weight recently or if you’ve been battling your weight for may years, if you often feel cold when everyone else is complaining about the heat and if you’re always tired and feel like taking a nap instead of getting up and getting some exercise it may be that you have a slow metabolism.

The next question of course is “why is my metabolism slow”?

Well, that’s a great question! Since your metabolism is how your body takes in food and oxygen and uses it to fuel all of its biochemical reactions there are a lot of things that can slow it down.

In this post we’ll talk about five common reasons your metabolism could be slow including: thyroid hormones, history of dieting, size, body type and body composition, activity level, and lack of sleep. I’ve also included a tip that you can try for each one of these possible “metabolism busters”.

Plus I’ll share one of my delicious thyroid-loving mineral-containing recipes that you can make for breakfast or dessert. This is one of my favorite ‘go to’ recipes when I’m having a chocolate craving.

Why is My Metabolism Slow?

You may feel tired, cold or you’ve gained weight. Maybe your digestion seems a bit more “sluggish”. Or maybe you’ve been overweight since you were a child.

Family members and your doctor have been telling you for years to just eat less and get more exercise but you know that you’re following all the “rules” of weight loss and nothing is working. You’re convinced that you have a slow metabolism.

Why does this happen? Why do some people have a fast metabolism while others have a slow metabolism? Or maybe you always had a pretty good metabolism but now it seems to be slowing down; why do metabolic rates slow down?

What can slow my metabolism?

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, type and 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”. In the coming months I’ll be posting a series of articles that dives deeper into each of these common causes, as well as a few lesser known but equally important reasons why you metabolism seems to be slower than everyone else (and it most likely is slower for biological reasons so you can quit beating yourself up for being “weak” or lacking in willpower).

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 heredity, autoimmune diseases and mineral deficiencies (iodine or selenium for example).

Tip: Talk with your doctor about having your thyroid hormone levels tested. If the test results show your thyroid levels are within a normal range and there are no other reasons for your symptoms you might want to speak with your doctor about seeing an endocrinologist for more specialized, in-depth testing and a specific plan for treating thyroid issues.

Your history of dieting

When people go on extreme diets or simply lose weight their metabolic rate often slows down. This is because the body feels stressed or 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 body fat it can also lead to a reduction in lean muscle. As you know, more muscle means faster resting metabolic rate, but when you lose too much muscle along with the body fat your metabolic rate will automatically begin to slow down.

The other thing to remember is that smaller people simply need fewer calories. With very few exceptions, a 100 pound ballerina can’t eat as much as a 250 pound football player. When you diet and reach a new smaller size you need to remember that you can’t go back to eating the way you did before. Before, you were eating for the size you were. Now, you need to be eating for the size you are or want to be.

This is all just basic biology.

Tip: Make sure you’re eating enough high quality whole food to fuel your body and keep it functioning optimally without going overboard. Practice portion control and add weight training to your weekly routine (3-4 times a week). These three things will help keep your metabolism working at top speed.*

Your body size, body type 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 eating more and gaining weight is rarely the best strategy for increasing your metabolism.

Body type and body composition are two other key factors in determining how fast or slow your metabolism works. There are three main body types:

ectomorph (thin build, long and lean, faster metabolism)
endomorph (chunky build, short or stocky, wide hips, narrow shoulders, slower metabolism)
mesomorph (wide shoulders, narrow waist, rounded belly, “normal” metabolism)

Although almost everyone will gain weight if they consume calories in excess of what their body requires regardless of their body type, endomorphs have a tendency towards having a slower metabolism. This means they gain weight easily and have an even more difficult time losing weight (did you ever feel like you gain weight just by looking in the bakery window or at that pizza your friend doesn’t think twice about eating?).

…the amount of energy your body uses depends partly on the amount of lean muscle mass you have…the more muscle you have the more mitochondria you have, and the more mitochondria you have the faster your metabolism will run…

Muscles that actively move and do work need more energy (calories) and use more 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. Another very important reason for building lean muscle is the little energy factories that live in your muscles…your mitochondria. The more muscle you have, the more mitochondria you have. The more mitochondria you have, the more energy you have, the faster your metabolism runs and the more calories you burn.

Body type, mitochondria and metabolism are topics I’ll be covering in depth in my next post. I became deeply interested in these three things when I was studying for my Precision Nutrition certification. I came to understand the importance of all three in achieving healthy weight loss and weight maintenance and it is this understanding that has ultimately helped me to finally see progress in my own weight struggle.

Tip: Do some weight training to help increase your muscle mass which will increase the number of mitochondria (remember…they are little energy factories) and should help in speeding up your metabolism. As noted above, try adding weight training 3-4 days each week.*

Which leads us to…

Your activity level*

Aerobic exercise (walking, running, dancing, elliptical machine, etc.) temporarily increases your metabolic rate. Your muscles are burning fuel to move and do “work” and you can tell because you’re also getting hotter and your body temperature increases slightly.

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. Park your car at the end of the parking lot when you go shopping, or walk up and down the stairs on a 10 minute break at work. My favorite recommendation is to walk, walk, walk. Remember, our ancestors walked all day every day. We were built to walk. Since you found this post on The Morning Walk Effect website you probably already guessed that I firmly believe in a daily morning walk (outside whenever possible) as the foundation for natural weight loss, wellness and lifestyle change.

Tip: Try to incorporate a morning walk or some other type of regular activity into your routine 3 – 4 times a week (or more if you’re able). If you aren’t able to get outside first thing in the morning then afternoon or evening are better than not doing anything at all. You can really can do any activity that you enjoy that gets your body moving for 30 – 60 minutes at a time. For simplicity, walking is easiest to do.

There are many benefits to a daily morning walk. Don’t get me wrong, I like evening walks/exercise too, but I always seem to get better results when I’m mostly taking my walks in the morning. Weight loss seems to be effortless, I have better appetite control for the rest of the day, I feel energized and motivated for the whole day, it gives me a chance to plan my day which makes me feel organized and in control of my day instead of my day controlling me (which often leads to stress snacking).

I know a lot of people like to listen to music when they’re walking, running or working out but I find I’m a lot less stressed and I’m able to get myself organized for the day when I’m just listening to the sounds of nature and whatever else is going on around me, but definitely do what works best for you.

And if all that wasn’t enough, walking builds and strengthens leg muscles (very important as we get older) and current research shows that just being outside where there are trees or flowers can relax you and help reduce blood pressure.

Lack of sleep

This may seem like a strange place to start when talking about metabolism but there is plenty of research that shows the influence that sleep has on your metabolic rate and the general consensus is to get 7-9 hours of sleep every night.

Lack of sleep disrupts circadian rhythms and can lead to inefficient body regulation of energy balance (body fat), metabolism and appetite. Abnormal ghrelin and leptin levels – hormones that tell your body when it’s hungry or full – often go awry when you’re body hasn’t gotten sufficient good quality sleep (7-9 hours).

Another reason sleep is so important is that when we’re tired we tend to make fewer healthy choices throughout the day and we end up reaching for the quick-fix energy boost we need, often in the form of sugar-filled and processed, packaged snacks.

To get more (and better) sleep set a goal of what time you need to be in bed each night to get the recommended 7-9 hours. Turn off the technology one hour prior to bedtime and if you have to be on your devices try using one of those new blue light filtering programs which can help reduce the melatonin suppression that can occur when you’re exposed to blue light after sunset. Research has shown that the light emitted from your television, laptop and tablet, and even the little bit of light coming from your alarm clock and cable/DVR box, can disrupt melatonin production making it difficult to fall asleep and can possibly cause other health issues.

Another great idea to help you fall asleep is to keep your bedroom cool. Research has shown that reducing the temperature in your bedroom to 68F, or even cooler if you don’t mind, can make it easier to fall asleep because it helps slow the body down (plus, who doesn’t like being tucked under warm blankets in a cool room?). I find that keeping the temperature in my room right around 64-66F works like a charm to help me fall asleep.

Tip: Try to create a calming routine that allows at least 7 hours of sleep every night. Lights out, no technology, a cool room and lavender are all great for relaxing and helping you fall asleep. A good book (with a small reading light) helps too.

*NOTE – please be sure to check with your physician before beginning any exercise or diet program.

Chocolate-Chia Pudding

Click on the picture below for my delicious chocolate-chia pudding recipe. For a selenium rich addition (great for thyroid health) add 2-3 chopped Brazil nuts on top.