Multivitamins, despite being one of the most commonly used supplements worldwide, generally show little to no improvement in mood, immune function, and overall wellbeing for individuals already meeting their nutritional needs through food. One large trial indicated a small memory improvement in older adults taking a daily multivitamin, but this difference was minimal.
However, multivitamins may be beneficial during life stages with increased nutrient requirements, such as pregnancy, or when nutrient intake or absorption is lower. It is advised to consult a doctor or dietitian regarding the best options, as multivitamins are not standardised.
The best return on investment for nutrients comes from real food, including fruits, vegetables, whole grains, beans, nuts, seeds, dairy or fortified alternatives, and protein-rich foods daily. These provide a blend of vitamins, minerals, fibre, and plant compounds that supplements cannot fully replicate.
Creatine, a compound naturally produced by the body and found in small amounts in red meat and fish, is stored in muscles to provide energy during short bursts of high-intensity exercise. When combined with effective training, adequate protein intake, and prioritised recovery, creatine may modestly help in lifting heavier weights or improving sprints. Unlike many nutrients, there is no practical food-first method to maximise creatine stores.
Collagen, the main structural protein in skin, tendons, and connective tissue, sees its production gradually decline from the mid-20s. Taking hydrolysed collagen peptide supplements daily for approximately three months may result in small improvements in skin hydration and elasticity, particularly for women aged 40 to 59. Collagen supplements are also being investigated for tendon and joint health, with some trials suggesting modest improvements, especially for specific groups like those with exercise-related joint injuries or high training loads. Prioritising overall protein intake and adequate vitamin C is crucial for collagen production.
In the UK, skin produces vitamin D from sunlight only between late March and early October. Outside these months, exposure to the sun is too weak, making low vitamin D more common in winter and among certain demographics year-round. While food sources are limited, it is recommended to supplement 10 micrograms (400 IU) daily during autumn and winter, primarily for bone health and supporting calcium absorption. High intakes should be avoided as vitamin D is fat soluble and can accumulate, potentially causing harm.
Magnesium supplements are marketed for various benefits, including sleep and muscle cramps, but evidence is often less conclusive than marketing suggests. Benefits are mainly observed in individuals with low magnesium intake. Many people in the UK fall below recommended magnesium intakes due to low consumption of nuts, seeds, legumes, whole grains, and leafy green vegetables. These foods also provide other key nutrients like fibre, healthy fats, vitamin E, and iron.
Electrolyte supplements, containing minerals such as sodium, chloride, and potassium, help regulate fluid balance. However, for most people, the science does not support their daily use for hydration. The body tightly regulates electrolytes, and balance is usually maintained through food and sufficient water intake, except in situations of significant fluid loss like long endurance exercise, heavy sweating, or illness. During heavy sweating, sodium and chloride losses can often be replaced by adding salt to meals or drinks.
Most people in the UK do not meet the recommendation of at least one portion of oily fish per week, which provides vital omega-3s, including EPA and DHA, along with protein, iodine, selenium, and vitamin D. For those who do not consume fish, algae-based omega-3 supplements offer a practical alternative, though plant-based omega-3s (ALA) are less efficiently converted to EPA and DHA.