‘Illness can be a real barrier to that well planned fitness regime (especially in those who push themselves too hard, or increase too quickly). Generally a healthy and balanced diet (avoiding extreme and fad diets) and appropriate management of exercise training load are recommended.
‘Evidence suggests that regular moderate activity is particularly beneficial for immune enhancement and reducing the risk of infection. More details are discussed in our recent paper: Nutritional and Physical Activity Interventions to Improve Immunity
‘It discusses some nutritional strategies. Unfortunately, the evidence for many is weak. Avoiding nutritional deficiencies with a balanced diet seems the most pragmatic recommendation. Including a variety of fruits and vegetables may help ensure adequate intake of essential nutrients with little risk of excess intake of any single nutrient.
‘Supplementation with individual nutrients is generally not recommended. Multinutrients may be beneficial for those with a pre-existing deficiency but not if normal dietary intake is sufficient.
‘Further benefit may be gained from some supplements including probiotics, bovine colostrum, and some plant-derived products (Echinacea, black elderberry, and some polyphenols) but only in specific situations/contexts. Individuals should consider their personal needs, use caution, and avoid the indiscriminate use of supplements.
‘But there are some extra gems to give the immune system a boost and help stave off those annoying winter illnesses. This year we published a paper showing that supplementation with Chlorella (a type of freshwater single-celled microalgae) may offer some benefit and give the immune system an extra boost during periods of intensified training.’
Dr Glen Davison, is a senior lecturer in the School of Sport and Exercise Sciences and his research interests include immune system function in athletes and the effects of nutrition on human immune function.