Q: Is there a way for someone with a slow metabolism to get a fast metabolism?
A: (Since this question usually relates to ease of weight loss – “people with fast metabolisms can lose weight or stay slim easy”, I will answer it in regards to that.) You will probably be surprised to hear that “naturally thin” people do not have higher resting metabolic rates, and that their resistance to weight gain is mostly because they have slow appetites. (“Naturally thin” are the tiny percent of people who struggle to gain weight.) Slow appetite = they get full faster and stay full longer.
Is There Such a Thing as a Fast Metabolism?
Here’s the full question: does anyone have a resting metabolic rate (calories burned without moving) that makes weight loss easy? In a word: No. Below is as brief of an explanation as I can give of the “no.”
Metabolism is the total calories that someone burns in a day. This is going to be a function of:
- Age: younger people tend to have more lean body mass (bones and muscles especially), and lean body mass burns more calories per pound at rest than fat does. Additionally, those who are young enough to still be growing vertically have the highest daily caloric burn because getting taller is very expensive.
- Muscle mass: after your major organs (brain, liver, etc) your muscle mass burns the most calories of any tissue at rest, and, obviously, at work.
- How much they exercise: exercise burns calories, and the more you do and the harder you work the more you burn. Exercise also increases your resting metabolic rate. The more intense, and the more exercise you do, the bigger the bump. The post-exercise bump isn’t as big as some marketers would like you to believe, but it is a factor.
- How much they move outside of exercise: researchers call this NEAT (non-exercise activity thermogenesis), and normal people call this “step count.” 2,000 steps per day burns very little, while 10k, or 15k per day can make losing or managing your weight much easier.
- Gender: men have 40-50% more muscle mass than women do, and about 10% less body fat at the same level of leanness. (A man at 20% body fat looks similar, in terms of “tone” or “leanness” as a woman at 30%.). The additional muscle mass and reduced fat mass make a big difference in how many calories men and women burn at rest and at work.
- Protein intake: The higher the % of protein in your diet the more calories you burn in digesting your food. The calories spent in digestion will never exceed the calories in your food. The calories spent in digestion are called TEF (thermic effect of food). Protein has a TEF of 20-30%, carbs have a TEF of 5-10%, and fat has a TEF of 0-3%.
- Thyroid status: if you have low thyroid function (like I do), this can drop your energy expenditure 10+% at rest, and even reduce how many calories you burn during exercise. Medication does seem to help, but probably only restores 1/3 to 1/2 of what was normal… seems unfair, but if could be worse – it could be 0%.
The biggest factors are gender, age, body weight and muscle mass levels. When you compare people who are similar in these factors their resting metabolic rates are nearly identical.
When I was 240 pounds, I definitely wished I had a “faster metabolism” like I (assumed) my thinner friends had, but, in reality, my wishes were about making an excuse for myself and throwing a little pity party. I felt better when I told myself that people who were more successful at managing their weight only had their success because they were luckier than me.
Bottom Line
Since nobody actually has a resting metabolic rate that is fast enough to make weight gain impossible, nor weight loss “easy,” then, by definition, it’s not something you can emulate.
The 1-2% of the population who struggle to gain weight are that way because of their slow appetites – they get full quickly and stay full longer. Furthermore, when you are comparing people of the same gender, body weights and muscle mass levels, our resting metabolic rates are essentially identical.
So, don’t waste your time being upset about, nor chasing things that don’t exist (i.e. a “fast metabolism”). The good news is that you can increase how many calories you burn by increasing how much you exercise, your daily step count, adding muscles mass, etc.
Coach Josef Brandenburg — ACE | NASM | Precision Nutrition | Training Peri and Menopausal Women |Functional Kettlebell Training | 28 years coaching | Specializes in strength training for women over 40.
Josef Brandenburg, best selling author, is the co-owner and a coach at True 180 Personal Training, Charlotte’s most effective personal training studio for women since 2016. With decades of experience and multiple certifications, he shares his research with you!