Jane Nodder looks at the vitamins and minerals that endurance runners need in part 7 of our Marathon Training Nutrition Plan.
For a complete table of Sources of Food for Vitamins and Minerals click here.
Now that we have looked at the key macronutrients – carbohydrates, proteins and fats – we can turn our attention to two other groups of essential nutrients – vitamins and minerals, known collectively as ‘micronutrients’. Vitamins are complex, organic substances that we need in very small amounts - milligrams (mg) or micrograms (mcg/µg) - for a whole range of body functions. We need to get most vitamins from the diet as they can’t be made by the body. Vitamins have a number of very important functions. Some are co-factors in enzyme activity, others act as antioxidants preventing damage from oxygen and others, such as vitamin D, are pro-hormones. If we lack certain vitamins due to a poor diet or a health condition such as malabsorption, we can develop certain symptoms or even deficiency disease. Vitamins are referred to either by their letters or by their chemical name, and are traditionally classified by their solubility into ‘fat soluble’ (vitamins A, D, E and K) and ‘water soluble’ (B vitamins and vitamin C). The fat-soluble vitamins are stored in the body for longer periods of time, whilst water soluble vitamins tend to be excreted more easily. Minerals are inorganic substances required for bones and teeth, other body fluids and tissues, enzyme systems and the nervous system. Like vitamins, the ‘major’ minerals are needed in larger amounts (above 100mg per day) and include calcium, phosphorus, magnesium, sodium, potassium and chlorine. Other ‘trace’ minerals are required in smaller amounts (less than 20mg/day) and include iron, zinc, iodine, fluoride, selenium and copper. Endurance exercise and micronutrient statusMicronutrients are required for many metabolic pathways in endurance, and although athletes can generally meet any need for additional vitamins and minerals through a higher energy intake, the status of some micronutrients - e.g. calcium, vitamin D, the B vitamins, iron, zinc, magnesium, and the antioxidants vitamins C and E - is frequently of concern in athletes. The table below shows:
Micronutrients and Endurance Athletes
Endurance athletes may need up to double the generally recommended levels of B vitamins. In particular, severe deficiency of vitamin B12 and/or, folate, may lead to anaemia and reduced performance. Runners who increase their energy intake by increasing their intake of refined carbohydrates without paying attention to the overall quality of their diet may need additional vitamin B1 (thiamine).
Watercress, squash, yeast products, asparagus, mushrooms, peas, lettuce, peppers, cauliflower, cabbage, tomatoes, beans, broccoli, pumpkin, beansprouts, mackerel, milk, meat, tuna, chicken, salmon, lamb, tomatoes, dairy products, eggs, lentils, sardines, grapefruit, water melon, corn, wheatgerm, peanuts, sesame seeds, hazel nuts, oranges, leeks, cod, kale, trout, soya beans.
Vitamin D is required for optimal bone health, for the immune system and to reduce the risk of injury, inflammation and impaired muscle function. Vitamin D status varies a great deal and some runners, particularly those training in northern latitudes such as in the UK, may have an increased risk of poor status, especially if they do not eat foods containing, or fortified with, vitamin D. Supplementation may be needed to reach a minimum serum concentration of 32ng/mL.
Male and female adults in all age groups. Vegetarians.
Vitamin E can reduce levels of lipid damage that can occur during endurance exercise. It may also reduce exercise-induced DNA damage, inflammation and muscle soreness during recovery. Currently, there is no official UK reference standard for daily Vitamin E intake, although the Department of Health states that intakes above 3mg for women and 4mg for men are safe. In 2000, the USA Institute of Medicine set a Recommended Daily Allowance (RDA) for vitamin E of 15mg/day.
Male runners particularly in the over 55 age group.
Sunflower seeds, almonds, walnuts, roast peanuts, bananas , olive oil, sunflower seed oil, spinach, carrots, tomatoes, beans, peas, tuna, green leafy vegetables.
There is little clear evidence for the benefits of vitamin C supplementation in runners even though athletes may be advised to supplement between 100-1000mg /day. Vitamin C is known to support the immune system and to help the body respond more effectively to stress hormones and anti-inflammatory chemicals. However, studies have not found any particular benefit of vitamin C supplementation for muscle damage or for reducing the upper respiratory tract infections in moderately trained marathon runners. Indeed some evidence suggests that vitamin C supplements in athletes can actually impair immune function, reduce endurance capacity and lower training efficiency.
Beansprouts, broccoli, cabbage, potatoes, cauliflower, kale, peppers, kiwi fruit, parsley, spinach, sprouts, turnips, melon, cantaloupe, honeydew, loganberries, grapefruit, lemons, watercress, strawberries, raspberries, tangerines, tomatoes, liver
Calcium, along with other minerals such as magnesium and boron and vitamins D and K, is particularly important for bone health and for preventing injury.
Female runners particularly in the 18-29 age group. males runners in the 50-59 age group. Vegetarians.
Green leafy vegetables, cauliflower, broccoli, parsley, watercress, parmesan cheese, feta cheese, ricotta cheese, molasses, tofu, canned sardines, salmon and pilchards, yoghurt, milk, enriched soya milk,
kidney beans, lentils, dates, raisins, seeds e.g. pumpkin, sesame and sunflower, nuts and their milks e.g. almonds, hazelnuts, oat milk, seaweeds, baked beans
Distance runners need about 70% more iron than the general population and so it’s not surprising that many runners, particularly women, vegetarian athletes and blood donors, can be low or deficient in iron. Iron is particularly important to help transport oxygen to cells and for muscle function.
Female runners especially those in the 18-39 age group.
Beef (lean), cheddar cheese, chicken and chicken liver, cottage cheese, eggs, lamb, liver, pork, salmon, walnuts, artichokes, aubergines, avocado, broccoli, carrots, cauliflower, celery, mushrooms, red meat, fresh green peas, green leafy vegetables, brown rice, currants, dates, dried prunes, figs, raisins, apples, sunflower seeds, bananas, blackberries, cherries, spinach, clams, oysters, chicken liver, sardines canned in oil and turkey.
Female athletes are at greater risk for low zinc status which can impact cardiorespiratory function, muscle strength and endurance. Zinc status is notoriously difficult to measure.
Oysters, ginger root, pork chops, lamb chops, chicken, haddock, liver, cauliflower, cucumber, lettuce, potatoes, carrots, Brazil nuts, buckwheat, hazel nuts, oats, peanuts, almonds, walnuts, rye, egg yolk, milk, sardines, tuna.
Females in the 18-29 age group.
Almonds , aubergines, apples, Brazil nuts, broccoli, blackberries, cashews, peanuts, chicken, crab, Cheddar cheese, milk, cabbage, carrots, celery, fresh peas, garlic, green beans, mushrooms, lettuce, onions, parsley, sweetcorn, potatoes with skins, tomatoes, dried apricots, dried dates, dried figs, dried prunes, grapes, green leafy vegetables, raisins.
Potassium and sodium balance electrolyte and fluid levels helping to avoid cramp and dehydration during intense exercise. Potassium also helps to build muscle. Levels of both minerals can fall during endurance exercise which is one reason for consuming a sports drink containing sodium (0.5-0.7g/L), potassium (0.8-2.0g/L) and carbohydrate during competition and training sessions lasting more than 1-2 hours.
Sodium: females, aged 18-29, males, aged 50-59.
Which foods for which vitamin and mineral?Remember, one of the most important actions for obtaining sufficient micronutrients in your diet is to include a wide variety of foods. Check the table above or click here for more Sources of Food for Vitamins and Minerals for more information on which foods to add to your diet to obtain specific vitamins and minerals.
Use of nutritional supplementsVitamins and minerals are certainly important for good health and to train and compete successfully. It is often stated that athletes do not need additional nutritional supplements if they eat a varied diet with sufficient energy to maintain their body weight and meet at least the minimum requirements for all the micronutrients. And more is clearly not always better when it comes to the benefits that can be gained from nutritional supplements. However, it might be important to consider a multivitamin and mineral supplement for individuals who restrict their energy intake or eliminate certain foods or food groups or who are ill or recovering from injury. Single-nutrient supplements may also be needed for a specific medical or nutritional need (e.g. to correct iron deficiency anemia). Make sure you seek advice from a suitably qualified nutrition professional if you are considering taking nutritional supplements particularly if you take prescribed or over-the-counter medication. Contact us at info@nutriworks.co.uk for more information.Actions for this week
And if you need more help to build your personal nutrition plan, email Jane Nodder at info@nutriworks.co.uk for details of individual nutrition coaching services for runners.
About Jane Nodder and Nutriworks
Jane Nodder works as a nutrition lecturer and clinic tutor on the MSc and BSc (Hons) Nutritional Therapy programmes at the University of Westminster, London. A qualified UK Athletics Leader in Running Fitness, Jane started running in 1986. As a club runner she runs track, cross-country, road, trail and endurance events and has completed eleven marathons, taking her PB from 4h21 to 3h37. Through her business, Nutriworks, Jane coaches groups and individuals in running and in translating general sports nutrition guidelines into practical, individualised nutrition programmes.
In 2010, Jane was awarded the Complementary & Alternative Medicine (CAM) Award for Individual Excellence in Nutritional Knowledge, and in December 2011 she gained the Yakult Prize for Outstanding Student of the Year for the MSc Nutritional Medicine at the University of Surrey.
For more information about running and nutrition coaching services from Nutriworks, including details of an introductory seminar ‘Nutrition for Marathon Runners’ on 18 February 2012, visit www.nutriworks.co.uk or contact Jane directly on 07850 705848 or email info@nutriworks.co.uk
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