Research, evidence, and sources
What this page is for
If worry, panic, or a low mood is getting in the way of daily life, that is a conversation with a clinician. Shopping is not a substitute for that.
What the reviewed sources say
“However, clinical trials show that taking vitamin D supplements does not prevent or ease symptoms of depression.”
Low mood and depression are not the same thing as an everyday wish to feel calm, and this page does not treat them as the same. The vitamin D fact sheet says some studies have linked low blood levels of vitamin D with a higher risk of depression. Clinical trials, the page says, show that taking vitamin D supplements does not prevent or ease symptoms of depression. That finding is a reason not to shop vitamin D for mood. It is not a proof about every other ingredient, and it is not a product suggestion.
Vitamin D — Consumer Fact Sheet NIH Office of Dietary Supplements. Updated 2022-11-08. Retrieved 2026-10-07.
“Magnesium is a cofactor in more than 300 enzyme systems that regulate diverse biochemical reactions in the body, including protein synthesis, muscle and nerve function, blood glucose control, and blood pressure regulation.”
Magnesium’s fact sheet describes jobs in nerve function, muscle function, and hundreds of enzyme reactions. It does not report a trial in which a magnesium supplement produced calm. A biological role is not a mood result.
Magnesium — Health Professional Fact Sheet NIH Office of Dietary Supplements. Updated 2026-01-06. Retrieved 2026-10-07.
The fact sheets cited on this page do not establish that a supplement produces calm. The fact-sheet index is there if you want the wider library. No product list on this page means we do not have support to suggest one. It does not mean science has proved that nothing could help.
Dietary Supplement Fact Sheets NIH Office of Dietary Supplements. Retrieved 2026-10-07.
How to compare a label
“The nutrition label for a dietary supplement is called a “Supplement Facts” panel.”
Start with the Supplement Facts panel. The FDA’s labeling guide uses that name for a dietary supplement’s nutrition label.
Read the ingredient name, the amount per serving, and the serving size. A blend that lists several ingredients is a different product from a bottle that is only one of them. The price on a retailer card is the package price, not a price per serving, and a sale ribbon is not a checked comparison price.
- Dosage unit converterConvert grams, milligrams, and micrograms. IU converts only when the vitamin form is known.
- Price per servingSee what one serving costs from the container price and the servings on the label.
- Cost per labeled amountSee what a labeled amount of an ingredient costs. A second product is optional.
- Daily nutrient targetsPublished folate, magnesium, and vitamin A figures for a life stage.
Dietary Supplement Labeling Guide: Chapter IV. Nutrition Labeling U.S. Food and Drug Administration. Retrieved 2026-10-05.
Labels you can open
These lists match a published ingredient. Opening one is not a suggestion that the ingredient meets this goal.
Sources
- Vitamin D — Consumer Fact Sheet NIH Office of Dietary Supplements. Updated 2022-11-08. Retrieved 2026-10-07.
- Magnesium — Health Professional Fact Sheet NIH Office of Dietary Supplements. Updated 2026-01-06. Retrieved 2026-10-07.
- Dietary Supplement Fact Sheets NIH Office of Dietary Supplements. Retrieved 2026-10-07.
- Dietary Supplement Labeling Guide: Chapter IV. Nutrition Labeling U.S. Food and Drug Administration. Retrieved 2026-10-05.