You can find a good article on metabolism here:
https://www.vox.com/2018/9/4/17486110/metabolism-diet-fast-weight-loss
"Metabolism" is one of those terms thrown around recklessly without most people understanding what it means. There are lots of products, books, posts, diets, systems, etc., that claim they'll help people lose weight by "speeding up" or "boosting" metabolism. Most of this is nonsense (often from people who should know better). Any "boost" is minuscule and transitory.
People can sometimes blame a slower metabolism for extra caloric intake. We're really bad at estimating how much we eat and tend to overlook lots of little things (like sauces) that add up and lead to increased body fat. It's not that we're lying about it; it's just one of those human foibles.
As the author of the article found, "slow metabolism" is rarely a thing. Yes, it does slow down as we get older (which surprises no one over 40). And dieting--particularly extreme dieting--can slow it down too. But while such things can make it more challenging to shed unwanted pounds, it's not even close to impossible (although it can seem that way).
It's important to remember that metabolism is very complex. It's not just one thing; it's happening in every cell of our bodies and has all sorts of factors affecting it and affected by it. For me, this is the money quote from the article:
The big theme in many of these studies: Our metabolism silently shifts under new conditions and environments in ways we’re not usually aware of.
Trying to eat less might work for a while then lead to hunger pangs that undo (at least) any progress with fat loss. (Sound familiar?) Or it might lead to decreased energy for activity so we wind up burning fewer calories to make up for the reduced intake. The same goes for increasing activity: it can result in increased hunger and so increased calorie consumption.
One exception on the activity side is strength training. Building muscle increases our resting metabolic rate, but not by much and again it may be accompanied by increased hunger.
This might all sound kind of hopeless and depressing but that's not the point at all. Rather, I think it's important to understand (generally) the role of metabolism in maintaining a healthy weight. Otherwise we can fall into the trap of giving up by blaming a mythical "slow metabolism" or fall into the dieting trap (lose it then get it back) or have unrealistic expectations for exercise as a weight loss tool.
Here are some things you can do to help make the most of your metabolism:
- Find what works for you, and that includes changes you can maintain. Some people have success with different dietary changes or programs. Some adapt well to forms of increased physical activity. Try sensible changes that will stick.
- Don't be in a hurry. Small changes make big differences over time. For example, “it only takes maybe a 100 calorie-per-day difference between food intake and energy expenditure over a few years to gain 10 pounds.” Same goes for losing it.
- Strength training is great for lots of reasons. Even if it doesn't help you maintain a healthy weight, do it.
- There's no magic answer, no secret metabolic booster. "If it sounds too good to be true..." Small dietary changes and a sustainable strength program will do more than any overpriced supplement or DVD set.
There's no use worrying about "fast" or "slow" metabolism. Or listening to folks talk about "boosting" it almost as if they don't understand what it is.
Be seeing you.
-gary