Nutritional tips to keep winter ills at bay

AS WE approach winter most people¸ and particularly parents of little ones, start to worry about picking up colds and flu. The more we can do to prevent ourselves getting sick the better.

Diet and nutrition play a significant role in determining the strength of our immune systems. There is increasing evidence indicating the effect that nutrition can have on foetal programming, as well as on the first two years of a child’s life.

The thinking is that infants and children who are malnourished in the early stages may be more susceptible to diseases and have weakened immune systems later.

The more we can improve on nutrition, starting from pregnancy, infancy and extending through childhood, the greater the long-term benefits into adulthood.

As our immune cells are based on proteins, it is important to consider the quality and quantity of protein we are including in our diets. The integrity and function of our immune cells can be compromised if we do not consume sufficient dietary protein, making us more susceptible to catching infections.

Most people eating a varied diet based on fresh foods do ingest sufficient protein, but concern lies with people who may be following vegetarian or vegan diets, and those who place reliance on processed and convenience foods.

If animal products are excluded from the diet, most food intake tends to come from plant-based sources, which do not always contain all the essential amino acids required.

Vegetarians and vegans need to therefore ensure that their diets provide a wide variety of plant-based options, and include alternative protein sources, as well as possibly a protein-based supplement. This is particularly important for children and athletes.

Processed and convenience foods do not contain a good quality source of protein. For example, many deli meats and sausages contain only 60% animal meat compared to a fresh piece of chicken or meat that is 100% animal meat. People who regularly use processed foods will therefore be compromising their total protein intake.

Our antioxidant capacity is another important variable to consider. To avoid compromising our innate antioxidant capacity, we need to ingest sufficient dietary antioxidants. These should preferably be from fresh fruits and vegetables; however a daily supplement is also a worthwhile consideration. Dietary antioxidants include vitamins A, E and C and the mineral manganese, which has antioxidant properties.

Probiotics can also contribute to the immune system. A good gut colonisation of probiotics ensures that the integrity and function of the gut is maintained.

Our gut is one of the major defence barriers against external pathogens,and as such forms part of our immune system. If this gut integrity and function is in any way compromised we run the risk of external pathogens translocating into our circulation, where they can cause problems.

Babies and children have a natural colonisation of probiotics in their gut as a result of natural delivery and breast milk, as well as exposure to the outside world.

Foods that naturally contain probiotics are those that have been cultured or fermented. For example, yoghurt, maas and foods like kimchi (a fermented cabbage dish from Korea).

There is evidence to suggest that a probiotic supplement can help to boost and maintain gut integrity and therefore our immune system. If taken daily in the right doses, and provided one is healthy and free of any underlying gastrointestinal problems, it generally does more good than harm.

Extra caution must be exercised when taking antibiotics that kill all bacteria, good and bad, resulting in an almost “sterile” gut. A course of probiotics taken after antibiotics can help recolonise the gut faster than it would do so on its own.

Remember though that probiotics are live organisms; they need to be able to survive the digestive enzymes of the stomach and reach the colon intact, where they can exert their effect.

Of greater possible benefit is to ensure an adequate intake of prebiotics (food for the probiotics). Breast milk comprises 1% prebiotic by comparison with most South African infant formulas that do not contain any.

Prebiotics are found naturally in fresh foods containing fibre and in dairy products. Alternatively there are prebiotic supplements. Providing food for the probiotics can contribute to an adequate gut colonisation.

Everyone should however seek professional advice before taking any of the above supplements. Remember that more is not always better, and to avoid unnecessarily overdosing on nutritional supplements.

• Kerry Gibson is a dietician specialising in paediatric and sports nutrition.