Multivitamins, probably one of the most widely available dietary supplements, with variations to suit all budgets, as well as ones targeted at specific groups (children, pregnant women, athletes…). There is, however, some disagreement about how necessary they are if you are consuming a healthy, varied diet with lots of fruits and vegetables, which should be your first priority before buying any supplement regardless.
Before we go into multivitamins, I think one obvious flaw that we can point out is that the dosages are quite generalised. Based off average requirements for the average person, it might be a good idea to look at your needs in a little more detail before you pick just any product off the shelf to get the most benefit.
Vitamins, along with minerals and electrolytes, come under the bracket of ‘micronutrients’. These are molecules which do not provide energy (calories) but are essential for our health and wellbeing from immune function to energy metabolism. We tend to get them from our diet primarily, but supplementation can be an option to fill the gaps and prevent deficiencies. One argument for choosing a multivitamin over just the vitamin that you feel you may be lacking, is that micronutrients often have to work together to be effective.
We can group vitamins into:
Fat soluble; A, D, E, K
and
Water soluble; B complex and C
B vitamins
There are 8 B vitamins, a common one which you may have heard of (women especially) lacking in, is vitamin B12.
B vitamins are involved in energy metabolism, therefore athletes might need slightly more than sedentary individuals
Vitamin C
Commonly supplemented for its links to immune health
no long term risks associated with overdose
Vitamin D
The vitamin which we often use to excuse laying out in the sun for too long on holiday!
Can be found in oily fish, red meat and egg yolks
Vitamin D is a hormone and nutrient
Vitamin D works with calcium, linking it to bone health
The prevalence of vitamin D deficiency is high, especially in darker, colder countries such as the UK
Children from the age of one year and adults need 10mcg of vitamin D a day according to NHS recommendations
Vitamin E
Found frequently in skin products due to its role in protecting cells from free radicals
Low fat diets increase risk of deficiency
Doses larger than 1000 mg have been linked to blood clotting
Vitamin A
Often comes from animal sources (eggs, milk, fish...)
May need to be supplemented in vegan diets
Adult NHS recommendations are:
0.7mg a day for men
0.6mg a day for women
Too much may affect bone health and be dangerous in pregnant women
Vitamin K
Needed for blood clotting
found in leafy greens and vegetable oils
Adults need approximately 1mcg a day of vitamin K for each kilogram of their body weight (NHS, 2017).
Extremely large doses may cause liver damage or anaemia
Summary
Don’t let the risks of overdose put you off too much. While they are important to be aware of to prevent the ‘more is better’ mindset, no single, tested multivitamin along with a healthy diet should take you into those extremes. There are plenty of reasons why it is a great idea to invest in a supplement, but you should also consider what, in particular, you are looking to increase in your intake before just buying anything.