Guide

Vitamins and supplements for the immune system

Prepared by the LekCheck team · Last reviewed: 2026-06-29 · How we create our content

A balanced diet, sleep and exercise are the foundation of a good immune system; supplements can complement but do not replace a healthy lifestyle. Below are the commonly sought ingredients for immune support; choose one to compare products and prices. Some supplements can interact with medicines or affect laboratory tests.

This guide was prepared by the LekCheck team and has not been reviewed by a doctor or pharmacist. This article is for general information only and is not medical advice, diagnosis, or treatment. Do not start, stop, or change any treatment without consulting a doctor or pharmacist.

Vitamin C and zinc

Vitamin C (ascorbic acid) and zinc are among the most used supplements during the cold months. For each supplement there are recommended daily amounts and upper intake limits.

Vitamin D

Vitamin D (cholecalciferol) is often taken for a deficiency, especially in winter. The dose depends on individual needs; for high doses, consult a doctor.

What to bear in mind

Symptoms of a "weak immune system" do not always mean a real deficiency, and supplements do not treat infections. In pregnancy, breastfeeding, chronic disease or when taking medicines, consult a doctor or pharmacist.

When to see a doctor

See a doctor for frequent or severe infections, prolonged fatigue, unexplained weight loss or other worrying symptoms, rather than relying on supplements alone.