Micronutrient deficiencies. A thing of the past?

We’ve all probably heard of scurvy. The Horrible Histories-esque disease suffered by sailors back in an era most of us now only recognise thanks to Pirates of the Caribbean, caused by a lack of vitamin C in the diet.

Although scurvy is now pretty rare in high income countries, micronutrient deficiencies still exist, and are still a major cause of global malnutrition. The cost isn’t just a matter of life quality and increased mortality, but is also an economic one, with the effects of deficiency diseases still holding back millions from reaching their full potential.

What we talk about when we talk about micronutrient deficiencies nowadays

Perhaps unsurprisingly, those scurvy-ridden sailors get less of a look in these days. Instead ‘hidden hunger’ is the term used to describe the situation where the food people eat doesn’t provide all the micronutrients (vitamins & minerals) that we need for optimum health; even if they’re still getting enough calories for their daily energy requirements.

This is particularly common in low income countries where people are dependent on certain foods above all else. For example those dependent on white rice in several Asian countries, and tubers like cassava in many Sub-Saharan countries.

But before you stop reading, this is a global issue. Micronutrient deficiencies are still around and about in high and middle-income countries too. So here are a few of the most common micronutrient deficiencies that exist today, and how to eat to avoid them.

1. Iron

Iron is the world’s largest micronutrient deficiency, affecting an estimated 1.4 billion people worldwide according to the WHO. Yes, that’s right. Over a BILLION. Disproportionately affecting women thanks to blood-loss from that time of the month, iron-deficiency anaemia has a significant impact on foetal development, life quality, and economic productivity. To channel Susie Orbach, iron, as much as fat, is a feminist issue.

Common symptoms of iron deficiency anaemia include:

·       tiredness and lack of energy

·       shortness of breath

·       noticeable heart palpitations

·       a pale complexion.

As the best dietary source of iron is found in red meat, if you follow a plant based diet or are a menstruating female, it’s well worth keeping an eye on your iron intake or considering a supplement if you’re diagnosed as anaemic.

2. Vitamin A

Here’s a staggering fact. Vitamin A deficiency (VAD) is the leading cause of preventable blindness among children globally. We need vitamin A for many things, but it’s particularly important for normal vision, maintaining healthy skin and tissues, and a strong immune system.

VAD is most common in low income countries, where it can have a devastating effect on young children in particular, with symptoms including:

·       night blindness

·       dry or sore skin and lips

·       a weakened immune system, leading to a higher mortality rate for infections such as measles

Foods rich in Vitamin A include liver, fish, dairy products (milk, cheese, butter etc), and orange or yellow coloured vegetables like sweet potato, carrots, and mango. These all contain beta-carotene, a substance the body can cleverly convert into vitamin A.

3. Iodine

Although in developed economies we don’t hear an awful lot about this mineral, iodine deficiency was once a huge problem in many developing countries – in severe cases leading to goitres, where the thyroid gland swells to ridiculous proportions. In fact, the World Health Organisation describe iodine as the world’s most prevalent, yet happily also most preventable, cause of brain damage. Since 1993 iodine has been added to salt in many countries in a bid to prevent deficiencies which has been an unmitigated success. Incredibly cheap and yet very efficient, UNICEF estimates that some 66% of households globally now have access to iodised salt.

Which perhaps ironically, now leaves some European countries (where salt is not iodised) more at risk of iodine deficiency. Symptoms include:

·       Lethargy and tiredness, and constant fatigue.

·       Feeling cold (even on warm days)

·       Difficulty concentrating, slowed mental processes and poor memory.

·       Unusual weight gain.

In extreme cases the thyroid gland will swell (called a goitre), but you should consult a doctor immediately if you suspect you’re deficient. Foods naturally high in iodine are seafoods such as seaweeds and fish, and dairy products.

4. Calcium

Calcium is essential for healthy bones and teeth, helping to give them the structure and rigidity they need. Calcium requirements peak during adolescence what with all that growing, so it’s really important youngsters get the recommended amounts for their age groups. Rates of rickets, osteomalacia, and osteoporosis (where bones become softened, weakened, and/or more brittle) are all on the up, and the recent ‘clean eating’ trend with its misplaced enthusiasm for dairy-free seems to have impacted on intake among young adults. A recent National Osteoporosis Society survey found 20% of under-25's are cutting out or reducing dairy in their diet; a real cause for concern given that ‘peak bone mass’ is usually only reached by the late 20’s.

Symptoms include muscle spasms and cramps, and easy fracturing of bones.

Dairy products are the best dietary source of calcium, but green leafy veg, green beans, dried figs, legumes, nuts (especially sesame seeds), and fish with bones (like tinned sardines) also contain decent amounts of calcium.

5. Vitamin D

Calcium’s little brother, Vitamin D’s major function is helping to balance levels of calcium and phosphorus in the body, vital for creating strong, healthy bones and teeth. There is also increasing evidence to suggest D plays other important roles in the body and immune system. Although much of this evidence is yet to be conclusively proved, it does increasingly appear that many of us aren’t getting enough. Some academics believe as many as 1 billion of us globally could be deficient, which would make vitamin D one of the most common nutrient deficiencies worldwide.

While the numbers may not be quite this high, it’s certainly true that a lot of us are probably getting insufficient amounts. The problem is that diet alone is probably not enough to provide us with what we need – it ain’t called the sunshine vitamin for nothing. The most efficient way of getting vitamin D is via sunlight, as our bodies can convert sunlight on the skin into an active form of the vitamin.

Oily fish, egg yolks, butter, cod liver oil (sorry) and liver are all good dietary sources. Some breakfast cereals and breads are also fortified with vitamin D, but the best way of getting enough vitamin D is to spend 5-30 minutes in the sun at least twice a week, between 10 am and 3 pm, exposing your face, arms, legs or back. Be warned that sun block of 8 SPF+ or wearing lots of clothing will prevent the sun getting to your skin in adequate amounts, and in countries on a more northern latitude such as the UK, we don’t even get enough sun during the winter months (November to March) to make enough D. So although not by any means necessary for most vitamins and minerals, supplements can actually be very useful when it comes to vitamin D.

You should see your Doctor for testing if you experience any of the following deficiency symptoms:

·       Bone pain

·       Tiredness, or fatigue

·       Muscle weakness

·       Softened bones (leading to rickets in children)

And one final note

This blog (and in fact, the entire website!), is in no way intended to panic anyone about potential deficiencies. See it more as a reminder about how important micronutrients are for a healthy life, quite easily as important as the more talked about macronutrients.

References

www.who.int/nutrition/topics/WHO_FAO_ICN2_videos_hiddenhunger/en/

www.nhs.uk/Conditions/Anaemia-iron-deficiency-/Pages/Introduction.aspx

www.who.int/nutrition/topics/vad/en/

https://www.thyroidfoundation.org

BBC (2017). Dairy-free diets warning over risk to bone health.

http://www.nhs.uk/Conditions/vitamins-minerals/Pages/Vitamin-D.aspx