resurgence of rickets, a once-rare childhood bone disease caused by vitamin D deficiency, which suggests that modern dietary habits and government policies may not be providing adequate levels of this essential nutrient.
Cod liver oil, once a staple in households across the UK, was known for its high levels of vitamins D and A. In the 19th and early 20th centuries, it was widely administered to children to prevent rickets, a disease that weakens bones and can lead to seizures and heart problems. During World War II, the UK government issued free cod liver oil to children under five as part of a national health initiative.
The discovery in 1919 that vitamin D and calcium deficiencies were the cause of rickets led to widespread efforts to combat the disease. By the 1940s, the UK introduced mandatory fortification of margarine with vitamin D, and other countries followed suit with fortification programs for products such as milk, bread, and breakfast cereals. In the US, for example, fluid milk has been fortified with vitamin D since 1933.
Despite these fortification efforts, vitamin D deficiencies have persisted, particularly in regions with limited sunlight, such as the UK. The Met Office predicts that winters will become even rainier by 2070, further reducing exposure to sunlight, which the body needs to naturally produce vitamin D. Today, nearly 40% of children and 30% of adults in the UK are deficient in vitamin D during the winter months, with people of South Asian descent at especially high risk, according to public health nutritionist Judith Buttriss.
While governments around the world have sought to address this issue through food fortification, the UK encountered a setback in the 1950s. Cases of hypercalcaemia, a condition caused by excess calcium in the blood, raised concerns about vitamin D overdose, leading to a ban on most fortification efforts, with the exception of margarine and baby formula.
By 2013, the UK had discontinued the fortification of margarine, encouraging people to take supplements instead. However, this approach has not been widely adopted, and as a result, rickets has made a troubling return. In 1991, there were just 0.34 cases of rickets per 100,000 people under the age of 15 in England. But by the 2000s, those rates had begun to rise, and by 2011, hospitalisation rates for rickets were at their highest in five decades.
With these alarming statistics, experts are calling for a reassessment of vitamin D policies and potentially a revival of cod liver oil as a simple and effective way to combat deficiency and prevent the return of rickets on a wider scale.
