All adults (including women who are pregnant or breastfeeding) should consider taking a daily vitamin D supplement during autumn and winter. If you get little sunlight, you may need to take vitamin D supplements throughout the year.

Vitamin D is sometimes called the 'sunshine vitamin' because your body makes it when sunlight reaches your skin. It's also found in foods such as oily fish, egg yolks and some fortified breakfast cereals. But during the darker months, it can be difficult to get all the vitamin D you need from food alone. That's where vitamin D supplements can come in handy.

Branched-chain amino acids (BCAAs) are nutrients that the human body uses to build proteins for muscle tissue. We get all the BCAAs we need from the food we eat, but some athletes, bodybuilders and gym-goers take BCAA supplements to give their muscles additional support during and after workouts.

Scroll down to learn more about branched-chain amino acids, or select one of the following headings to skip ahead:

• What exactly are BCAAs?
• What do branched-chain amino acids do?
• Which foods contain BCAAs?
• Should I take BCAA supplements?