It’s a question I often get asked and it can be a little tricky to answer. A client may feel tired, cold or ‘feel’ that he has gained weight. His digestion might even seem a bit more “sluggish”.
Whatever the reason, the questions on a slowing metabolism remains the same; Why does this happen? And, more importantly; What can I do about it?!?!
How Does My Metabolism Slow Down?
First, we must understand that metabolism isn’t just “one” thing. It includes all of the biochemical processes your body conducts while converting nutrients and oxygen into energy. In fact, there are multiple factors that can affect the speed of your “metabolic rate” (which is measured in calories).
However, metabolic rate is even more complicated than prevalent “calories in calories out” philosophy. It's so complicated that I'm only going to list a few of the common causes of metabolic slow-down.
Examples of common reasons why metabolic rates can slow down:
Low Thyroid Hormone
A History of Yo-Yo Dieting
BMI & Body Composition
Lack of Sleep
I have briefly touch on each subject and have hopefully provided a bit more beneficial 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 with your doctor about having your thyroid hormones tested.
When people lose weight their metabolism can respond with a slow-down. It can trigger a “survival response” to the reduced intake of food. Sensing that food may be scarce, the metabolism adapts by burning only what it needs to sustain necessary life functions and “stores” the remaining calories to “survive” the “famine” of dieting.
While dieting can lead to a reduction in amount of overall weight, it can also lead to an overall reduction in lean muscle, too. Less muscle means a slower resting metabolic rate.
Tip: Make sure you're eating enough food to fuel your body without overdoing it.
BMI (Body Mass Index) & Body Composition
In general, larger people have faster metabolic rates due to the amount of energy required to fuel a larger body (but I’m sure I don’t need to tell you that gaining weight is “rarely” the best strategy for increasing your metabolism).
Muscles that actively move 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 you have.
Tip: Do some weight training to help increase your muscle mass.
Which leads us to...
Aerobic exercise temporarily increases your metabolic rate. The result: your muscles are burning fuel to move your body.
Even little things like 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 increase your overall activity level and improve metabolic efficiency.
Tip: Incorporate movement into your day in addition to regular exercise.
Lack of Sleep
There is plenty of research that shows the influence that sleep has on your metabolic rate. The general consensus is to get 7-9 hours of sleep every night.
Tip: Try to create a routine that allows at least 7 hours of sleep every night.
Because our metabolisms are highly complex, there are a lot of varying factors that can slow it down. The points I’ve listed are just a few of the more common. However, despite the “metabolic buster” tips I’ve provided, it is always a smart decision to seek the advice of your physician before embarking on a lifestyle change.
Until then – eat clean, breathe deep, and keep moving toward a better you!