You're considering taking dietary supplements for your well-being or performance, but one question is holding you back: will they make you gain weight? This concern is common and legitimate. The answer depends entirely on the type of product, its composition, and how you incorporate it into your diet.
Key takeaways:
To understand the impact of dietary supplements on your weight, it's helpful to keep a few simple principles in mind. Contrary to popular belief, most of these products have no effect on the scale. Here's the key information to consider.
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Weight gain depends on the overall calorie balance , that is, the balance between the calories you consume and those you expend, and not on a single product.
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Vitamins, minerals, probiotics and the majority of plant extracts do not provide significant calories and therefore cannot cause weight gain.
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Protein powders and weight gainers contain calories. They can lead to weight gain if they create a calorie surplus in your daily diet.
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Some formats, such as gummies or syrups, may contain added sugars . Their regular consumption can contribute to an excess of calories.
Supplements with no calorie impact on the scale
The vast majority of dietary supplements available on the market are not designed to provide energy. Their role is to supply specific micronutrients or active ingredients to support the body's functions. By definition, they therefore have no impact on your weight.
Vitamins and minerals: zero calories in sight
Vitamins (A, B, C, D...) and minerals (magnesium, iron, zinc...) are micronutrients. They are essential for countless biochemical reactions in your body, but they have no energy value .
In other words, they provide no calories . Therefore, vitamin D or magnesium supplementation cannot be responsible for weight gain.
Probiotics and plant extracts: what effect?
Similarly, probiotics , which act on the balance of your gut flora, or plant extracts (St. John's wort, ashwagandha, etc.) provide specific active substances. Their concentration is calculated for a physiological effect, not for energy intake. The caloric impact of a dose is therefore zero or so low as to be considered negligible in a daily diet.
|
Type of supplement |
Caloric intake per serving |
Impact on weight |
|---|---|---|
|
Multivitamins |
Zero or almost zero |
None |
|
Magnesium / Iron / Zinc |
Null |
None |
|
Probiotics |
Zero or almost zero |
None (may help with regulation) |
|
Plant extracts (non-appetite stimulants) |
Zero or almost zero |
None |
Proteins, weight gainers: supplements that have weight
Unlike vitamins and minerals, some supplements are sources of macronutrients and therefore contain calories. This is the case with protein powders and weight gainers, which are very popular in the sports world. Their effect on weight depends entirely on the context in which they are consumed.
Do protein powders (whey) cause weight gain?
A protein powder like whey is derived from milk and provides calories, just like a serving of chicken or fish. Its effect on your weight depends on your overall energy intake . If your goal is weight loss, a whey protein shake can help by increasing feelings of fullness and preserving muscle mass during a calorie deficit.
Conversely, if you consume protein powder in addition to an already rich diet and create a calorie surplus, you will gain weight. If this intake is combined with strength training, this weight gain will primarily result in muscle gain . Without adequate muscle stimulation, the excess will be stored as fat.
Weight gainers: specifically designed to gain weight
Weight gainers are products specifically designed to promote rapid muscle gain . They are composed of a blend of proteins and a large amount of carbohydrates, making them very calorie-dense. A single shake can provide several hundred kilocalories.
These products are intended for people who have difficulty gaining weight or for athletes with very high energy needs. Consuming them outside of this specific context almost always leads to weight gain, as it becomes very easy to exceed one's daily calorie requirements.
Omega-3, collagen, gummies: special cases
Some popular supplements raise questions due to their nature. What about omega-3s, which are fats, or gummies, often perceived as sweets? Here again, a simple analysis can clarify their impact.
Omega-3s: fats that don't make you gain weight
Omega-3s are fatty acids, therefore lipids. They contain calories. However, the amount consumed in a supplement is very small. For example, a daily dose of 3 fish oil capsules provides approximately 27 kcal. By comparison, a single tablespoon of oil to dress your salad provides nearly 135 kcal.
The caloric intake from omega-3 supplements is therefore minimal and largely offset by their benefits for cardiovascular and cognitive health. They do not contribute to weight gain as part of a balanced diet.
Collagen and gummies: beware of excess calories
Collagen is a protein. A dose of 10 to 15 grams provides between 40 and 60 kcal, which represents a negligible portion (2 to 3%) of daily energy intake. Its influence on weight is therefore very limited.
Gummies, however, raise another question. To achieve their pleasant texture and taste, manufacturers add sugar or glucose syrup. A 2.5g gummy can contain up to 2g of sugar. Although the calorie count per unit is low, regular and frequent consumption can contribute to an unnecessary and excessive sugar intake. It is therefore preferable to choose sugar-free forms such as capsules or tablets.
Frequently Asked Questions (FAQ)
Can vitamins like vitamin D or magnesium cause weight gain?
No, absolutely not. Vitamins and minerals are micronutrients that provide no calories. Their role is to support metabolism and cellular functions, not to provide energy. Therefore, they cannot in any way be responsible for weight gain.
Will whey protein powder make me gain fat or muscle?
It all depends on your overall diet and training. Protein powders contain calories. If they create a calorie surplus without strength training, you'll gain fat. If combined with training, they'll promote muscle growth. If used to increase satiety as part of a reduced-calorie diet, they can even help you lose weight while preserving muscle mass.
Do probiotics have an impact on weight?
Gut probiotics do not provide calories and therefore do not directly cause weight gain. On the contrary, by balancing the gut flora, they can have a beneficial effect on digestion and metabolism. A healthy gut microbiota is often associated with better weight management and reduced bloating.
Are there any pitfalls to avoid regarding supplements and weight gain?
Yes, the main pitfall is the added sugar in some formats. Gummies , syrups, or certain drinkable ampoules can contain a significant amount of sugar to enhance the flavor. Even if the calories per serving are low, regular consumption can contribute to an excess of sugar. Always opt for dry forms like capsules or tablets if you are watching your weight.
