Our associate nutritionist Abby has written this helpful 2 part series explaining all about vitamins and minerals.
KNOW YOUR VITAMINS – 2 PART SERIES
Read part 2 here
Part 1
Whether you are vegan, vegetarian, ‘flexitarian’ or an avid meat eater, variety and lots of micronutrients are key to a healthy, well-balanced diet. All food contains a mixture of nutrients in different quantities known as protein, carbohydrates (including fibre), fat, vitamins and minerals – otherwise known as micronutrients.
Micronutrients are essential for humans; they are required in small quantities throughout our life to carry out a range of physiological functions in our bodies (1,2).
Vitamins in fresh fruit and vegetables help to protect us against many diseases, including cancer and heart disease. Especially valuable are the vitamins which are known as antioxidants. This group is composed of beta-carotene (vitamin A) and vitamins C and E. They are found abundantly in plant foods. Another family of powerful antioxidants are called flavanols, including lycopene, found only in red fruits (e.g., tomatoes and red peppers) and vegetables. The reason why antioxidants are so important is that they are our main defence against damaging molecules called free radicals, which play a major role in diseases related to ageing. Antioxidants are the ‘heroes’ who neutralise the damaging free radicals, and so help to protect the body against diseases.
Unfortunately, micronutrient insufficiencies are not a thing of the past, even in the developed world in the 21st century. An increasing number of people consume calorie-dense, nutrient-poor food on a regular basis, which means that insufficiencies continue to exist (1,3).
There are 13 essential vitamins that our bodies need. Four of these are ‘fat-soluble’ and include vitamins A, D, E and K. Nine are ‘water-soluble’ which includes eight B vitamins and vitamin C.
Every day we produce bone, muscle and skin, heal wounds, free energy from the food that we eat, and regulate our immune systems. We also produce new red blood cells to carry nutrients and oxygen around our bodies.
It is the vitamins that we consume daily that help with such processes. Some of the most notable vitamins include:
Vitamins A, C and E We obtain vitamin A from foods containing beta-carotene, which we convert to vitamin A in the body. Beta-carotene is high in carrots, sweet potatoes, red/yellow peppers, tomatoes, green leafy vegetables, watercress, mangoes, apricots, pumpkins, cantaloupe melons, romaine lettuce. You’ll find high amounts of vitamin C in kiwi fruit, berries, and currants, fresh oranges, grapefruit, broccoli, spinach, cabbage, peas, blackcurrants, strawberries, green peppers and other fruits and vegetables. The antioxidant, vitamin E can be found in vegetable oils, wholegrains, tomatoes, nuts esp. almonds, asparagus, spinach, apples, carrots, celery and avocadoes.
The B vitamins These vital vitamins comprise B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin), B9 (folic acid) and B12 (cobalamin). Many B vitamins are involved in releasing energy from food and help to aid growth and repair of the body. They are widely available in wholegrains including wholemeal bread, brown rice and wholemeal pasta, yeast extracts (e.g., Marmite or low salt Meridian Yeast Extract with Added B12), pulses (peas, beans, lentils), nuts, seeds, dark green leafy vegetables, avocados and bananas. Many breakfast cereals are also fortified with B vitamins.
Vitamin B12 (cobalamin) This is required for the maintenance of a healthy nervous system and normal blood formulation. The liver has stores of B12 lasting up to three years and the body is also very efficient at reabsorbing it. Many common foods are fortified with B12 such as fortified breakfast cereals (double-check the ingredients label), yeast extracts, vegetable margarine and soya milk. Ensure a daily serving of these types of food or take a daily B12 supplement.
How does Micronutrient absorption take place and what are factors that influence it?
Fat-soluble vitamins enter the bloodstream via channels in the intestinal wall, which occurs after the fat-soluble vitamin- containing food has been digested in the stomach and small intestine. Many fat-soluble vitamins need proteins as carriers to be transported around our body. Fat-soluble vitamins can be stored in our liver and fat cells, being released when needed (4).
Water-soluble vitamins are absorbed directly into the bloodstream as food is digested and are easily transported around our body. Our kidneys regulate the level of these vitamins and remove excesses in the urine.
To assure yourself an ample supply of these valuable vitamins and minerals, be sure to eat a reasonably varied diet, including fresh fruit and vegetables, wholegrains (e.g., wholemeal bread and pasta, brown rice), all types of beans, as well as healthy snacks such as your favourite unsalted nuts, seeds or dried fruits (in moderation!).
Abigail is our associate nutritionist who aims to address myths around nutrition and empower her clients to make more informed nutritional choices, and educate her clients and help them regain control so they are able to make better decisions about their health and well-being.
“The truth is we ALL need guidance and support to change our lives and realise our goals.”
Abigail’s particular interests are in gut health, and she works on both weight management, diabetes and heart health. As well as supporting athletes and active individuals to meet their nutritional requirements.
If you'd like to know more, get your free nutrition assessment to get the best nutritional advice for you.
References:
1. Derbyshire EJ. Front Nutr. 2018;5:55.
2. World Health Organization. Micronutrients. Available online at http://www.who.int/nutrition/topics/micronutrients/en/. Accessed January 2020.
3. Peter S, et al. Nutrients. 2014;6:6076–94
4. Medical News Today. Vitamin A. Available at: https://www.medicalnewstoday.com/articles/320310.php#vitamin-a. Accessed January 2020.