Skip to main content
November 15, 2018

Why Lamu county is legislating rickets

The typical ‘black’ African has a skin type designated as skin type six. What this means is that they are dark-skinned and do not get sunburned easily.  A person with a skin type five is similar to an Asian living in Kenya. They may sometimes tan in the sun and may get sunburned a little but not much. Contrast that with skin type one or two where they almost always burn and never tan. Their skin remains pale but burns on contact with the sun’s rays. While anyone can develop skin cancer, those with skin types one and two are at the highest risk of developing skin cancer because their skin contains very little melanin, a natural compound which gives skin its colour.

Skin cancer is partly caused by UV radiation, which damages skin cells. The critical property of melanin is that it is an effective absorber of light and is able to dissipate over 99.9 per cent of absorbed UV radiation thereby protecting the body from the harmful effects. Living at the equator, the sun is present all day long, every day of the year. So most of us wisely avoid the midday sun, working early in the morning and late in the day. This habit introduces one of Africa’s favourite sayings, “killing two birds with one stone”. Not only is skin cancer risk reduced but the body gets vitamin D as well; provided of course that the skin is exposed to the sun especially in the morning hours. It would seem that African skin is perfectly adapted to tropical weather.

The migration of dark-skinned people into the northern hemisphere has led to some interesting findings. In North America, vitamin D deficiency is more prevalent among black African Americans than other Americans. Young otherwise healthy black African Americans do not have optimal 25-hydroxyvitamin D, which is what vitamin D is converted to in the body at any time of year. This is because the dark skin pigmentation reduces vitamin D production in the skin. In the weak northern hemisphere sun, this is a disadvantage. Luckily, vitamin D occurs naturally in some foods particularly certain fish, fish liver oils, and egg yolks but in relatively small doses. Time in the sun gives a minimum of 3,000 units of vitamin D compared to 100 units in a glass of milk. Fortified foods such as dairy and fats can increase the amount of vitamin D to about 400 units. Unfortunately for the same black African Americans, from puberty onwards they do not eat enough of these foods. Come to Africa and poverty dictates that food is always going to be a problem. Dairy products ranging from fresh milk to VAT expensive cheese are not readily available.

Vitamin D has a number of important functions in the body. We associate vitamin D deficiency with rickets because the body needs the vitamin for calcium metabolism essential in bone formation. But research suggests that vitamin D does a lot more in the body. Low blood levels of the vitamin have been associated with cognitive impairment in older adults; increased risk of death from cardiovascular disease; severe asthma in children and cancer. It has also been shown to play a role in the prevention and treatment of diabetes and hypertension. Therefore where there is a possibility of not getting enough vitamin D from the sun, all pregnant and breastfeeding women, infants and the elderly, those over 65 years are especially at risk of developing the conditions listed above.

Given this information it should be surprising that Lamu County Assembly is advocating for people to be covered up when in public. The reasons given are primarily that it is the culturally appropriate thing to do. The danger however is that if obeyed people will not get enough vitamin D. What is worse is that the rule would not affect the fast disappearing pale-skinned tourists. Their skin type means they need relatively fewer minutes, just 20-30 minutes of the sun on their face and forearms, to get their vitamin D dose. For a dark African, more time uncovered in the morning sun is needed. They may even need to be encouraged! Changing habits means that more of us spend time indoors than in yesteryear when fetching water and herding goats was the norm. Further evidence of this is provided by the high prevalence of vitamin D deficiency among adults in the Middle East where people cover up their bodies.

Kenya has some of the worst health indicators in the world. A primary function of county governments is to look after the health of citizens. Devolution is meant to lead to greater thought and investment in health and healthcare. Passing laws that weaken pregnant and breastfeeding women, children and the elderly is not a progressive way to improve Kenya’s health status.

Poll of the day