How long does it take to feel the effects of vitamins?

When results may become noticeable

Here’s how long it may take to feel the effects of certain vitamins and supplements:

• B7 (Biotin) – Commonly found in supplements for hair, skin, and nails. Evidence of effectiveness is limited. If you are deficient, it may take several months to notice improvements in nail, skin, or hair health.

• B12 – May start improving energy levels and reducing fatigue within a few days to weeks if you are deficient. Effects may appear faster if B12 is taken as a sublingual tablet.

• Vitamin D – Low levels may take weeks or even months to correct. Timing depends on baseline levels, supplement dosage, and whether you also get vitamin D from sunlight or food.

• Multivitamins – If generally healthy and without deficiencies, you may not notice significant changes. Improvements can appear in a few weeks for those lacking certain nutrients, especially if experiencing fatigue or low energy.

• Magnesium – Often taken for muscle cramps, migraines, or sleep support. Benefits can appear within a week.

• Omega-3 – Effects may take 6–12 weeks to become noticeable.

Factors that influence absorption speed

Type of vitamin

According to the journal Cureus, the time it takes to notice effects depends on the type of vitamin and whether a deficiency exists. Some vitamins, such as vitamin C, are quickly absorbed, so relief from symptoms like weakness may be felt within days to two weeks. Others, like vitamin D, require time to accumulate in the body to effective levels.

Nutrition

Nutrient absorption is generally best when you are well-hydrated and eating a balanced diet. Your body needs enough water to absorb water-soluble vitamins and enough dietary fat to absorb fat-soluble vitamins.

Fat-soluble vitamins, including A, D, E, and K, require dietary fat for absorption. Foods to include in your diet:

• Nuts;

• Seeds;

• Olive oil;

• Fish;

State of the body

Digestive or absorption-related health issues can make it harder for the body to process vitamins, slowing or reducing their effects.

Some conditions that may impair nutrient absorption:

• Anorexia nervosa;

• High stomach acidity;

• Inflammatory bowel disease;

• Vomiting;

How to know if vitamins are working

According to MedlinePlus, if you are not deficient, taking supplements may not provide benefits and could cause unwanted side effects, especially at high doses.

If you are taking vitamins to correct a deficiency, you may notice subtle improvements, such as:

• Better sleep;

• Improved mood;

• More stable energy;

• Stronger nails or hair.

This material is for informational purposes only and should not be used for medical diagnosis or self-treatment. Our goal is to provide readers with accurate information about symptoms, causes, and methods of detecting diseases. RBС-Ukraine is not responsible for any diagnoses that readers may make based on materials from the resource. We do not recommend self-treatment and advise consulting a doctor in case of any health concerns.