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What slows down metabolism?
Maintaining a high metabolism is vital to achieve weight loss and prevent weight regain.
Nevertheless, there are some typical lifestyle mistakes that can reduce your metabolism.
Consistently engaging in these habits can slow down weight loss and increase the risk of weight gain.
6 things that slow down metabolism
1. Eating very little calories
Consuming an insufficient amount of calories can significantly lower metabolism. While a calorie deficit is necessary to lose weight, it can be counterproductive if your calorie intake drops excessively low.
If you drastically reduce your calorie intake, your body recognizes the shortage of food and reduces the rate at which it burns calories.
Studies conducted on both lean and overweight individuals have demonstrated that consuming less than 1,000 calories per day can considerably affect your metabolic rate. Study 1, Study 2, Study 3, Study 4.
The majority of studies measure the resting metabolic rate, which is the number of calories burned while at rest. However, some studies also measure the total daily energy expenditure, which includes the calories burned during rest and physical activity over a 24-hour period.
According to a study, obese women who consumed 420 calories per day for 4-6 months experienced a significant decrease in their resting metabolic rates.
Furthermore, even after increasing their calorie intake over the next five weeks, their resting metabolic rates remained considerably lower than before starting the diet.
In a different study, overweight individuals were instructed to consume 890 calories per day. After three months, their total calorie expenditure, on average, decreased by 633 calories.
Even if the reduction in calorie intake is more moderate, it can still slow down your metabolism.
In a study involving 32 individuals over a period of four days, the resting metabolic rate of those who consumed 1,114 calories per day decreased more than twice as much as those who consumed 1,462 calories. However, both groups had similar weight loss results.
If you plan on losing weight by reducing calorie intake, avoid restricting your calories excessively or for extended periods of time.
2. Not consuming enough protein
Consuming an appropriate amount of protein is crucial for attaining and sustaining a healthy weight.
Apart from helping you feeling “full”, a diet filled with high protein foods can greatly enhance the rate at which your body burns calories according to these studies: Study 1, Study 2, Study 3.
The boost in metabolism that happens during the process of digestion is known as the thermic effect of food (TEF).
The thermic effect of protein is significantly greater than that of carbohydrates or fats. Research suggests that consuming protein causes a temporarily increase in metabolism by approximately 20-30%, compared to 5-10% for carbohydrates and 3% or less for fats.
While metabolic rate is bound to decrease during weight loss and persist to be slower during weight maintenance, research suggests that consuming more protein can help mitigate this effect.
One study involved participants who followed three different diets with the aim of maintaining a weight loss of 10-15%.
The group that consumed the highest amount of protein in their diet showed a decrease in their total daily energy expenditure by only 97 calories to maintain a 10-15% weight loss. In contrast, the groups that consumed less protein showed a decrease in their total daily energy expenditure by 297-423 calories.
To prevent a decrease in metabolism during and after weight loss, it was found in a study that people should consume a minimum of 0.5 grams of protein per pound of body weight (1.2 grams per kg).
3. Having an inactive lifestyle
A lack of physical activity can result in a notable decrease in daily calorie expenditure.
Many individuals have jobs that require prolonged sitting, which can have negative effects on their metabolism and overall well being.
Engaging in physical activity, whether through exercise or daily tasks like standing, walking, cleaning, or taking stairs, can increase the number of calories you burn, even if it’s not intense.
This type of physical activity is called non-exercise activity thermogenesis or NEAT.
One study revealed that a substantial amount of NEAT could lead to burning an extra 2,000 calories per day, but achieving such a high increase is not feasible for the majority of individuals.
In another study, it was observed that watching TV while sitting resulted in burning approximately 8% fewer calories than typing while sitting and 16% fewer calories than standing.
Using a standing desk or taking frequent breaks to walk around during the day can boost your NEAT and prevent a decrease in metabolism.
4. Lack of quality sleep
Getting a proper amount of sleep is important for overall health and wellbeing.
According to this study, getting insufficient sleep can elevate the risk of various health issues like heart disease, diabetes, and depression.
Sufficient sleep is important for maintaining a healthy metabolic rate and preventing weight gain. Several studies suggest that insufficient sleep may have the opposite effect. Study 1, Study 2, Study 3.
One research found that when healthy adults slept only 4 hours per night for 5 consecutive nights, their resting metabolic rate dropped by an average of 2.6%. However, their rate went back to normal after 12 hours of uninterrupted sleep.
Sleeping during the day instead of at night can worsen the negative effects of sleep deprivation by disrupting your body’s internal clock, known as the circadian rhythms.
One study conducted over a period of five weeks found that the combination of chronic sleep deprivation and disturbance in the body’s circadian rhythm led to an average 8% decrease in resting metabolic rate.
5. Consuming sugary drinks
Consuming sugary drinks is harmful to health and has been associated with conditions such as insulin resistance, diabetes, and obesity according to these studies. Study 1, Study 2.
The harmful effects of sugary drinks are largely due to their fructose content. Regular table sugar contains 50% fructose, while high-fructose corn syrup has 55% fructose.
Regularly drinking sugary beverages can have a negative impact on your metabolism and can slow it down.
In a study that lasted 12 weeks, overweight and obese individuals who drank fructose-sweetened beverages, making up 25% of their calorie intake while on a weight-maintaining diet, experienced a notable decrease in metabolic rate.
Another study found that there was no difference in the 24-hour metabolic rate between overeating high-fructose corn syrup and whole wheat. This contradicts the belief that high-fructose corn syrup may negatively affect metabolism.
Research has found that consuming high amounts of fructose can lead to increased fat storage in the liver and abdominal area. Study 1, Study 2, Study 3, Study 4, Study 5.
6. Lack of strength training
Weightlifting can prevent a decrease in metabolism.
Research suggests that strength training can help raise metabolic rate not only in healthy individuals but also in those who have heart disease or are overweight or obese. Study 1, Study 2, Study 3, Study 4
Building muscle through strength training can boost your metabolism because muscle tissue requires more energy to maintain than fat tissue. Therefore, having more muscle mass can increase your resting metabolic rate and help you burn more calories even when you’re not exercising according to these studies. Study 1, Study 2, Study 3.
A small amount of strength training can increase your calorie burn.
A study conducted over 6 months found that individuals who engaged in 11 minutes of strength training, 3 times per week, experienced a 7.4% increase in their resting metabolic rate and burned an additional 125 calories per day, on average.
According to research, not engaging in strength training can lead to a decrease in your metabolic rate, particularly during weight loss and aging. Study 1, Study 2, Study 3
Conclusion
Slowing down your metabolism by adopting certain lifestyle habits can lead to weight gain in the long run. It is advisable to avoid or reduce these behaviors as much as possible.
In addition, several easy way can boost your metabolism, helping in weight loss and weight loss maintenance.
