While there is a known link between vitamin D levels and bone metabolism – including rickets, osteomalacia, and osteopenia – the team behind the current study wanted to test suggested links between the sunshine vitamin and blood lipids.
Led by Sonja Soininen at the University of Eastern Finland the team performed a cross-sectional population study in more than 500 children – finding that those who had high levels of vitamin D in their blood plasma had lower total and low-density lipoprotein (LDL) cholesterol children who had insufficient vitamin D levels.
Writing in the Journal of Clinical Endocrinology and Metabolism, the researchers reported that the link between higher serum vitamin D levels and lower plasma cholesterol levels was independent of body adiposity, dietary factors, physical activity, parental education, and day length prior to blood sampling.
Moreover, hereditary factors that have previously been linked to serum vitamin D levels did not modify the observed association, they said.
Soininen and her colleagues said their findings demonstrate for the importance of following recommendations for vitamin D intake, including supplementation. They added while the major source of vitamin D comes from sunlight for many in the world, there are several populations in northern latitudes where sunlight alone is inadequate to maintain sufficient vitamin D levels.
While dietary recommendations can vary from country to country, the team noted that the most important dietary sources of vitamin D are fortified products such as dairy products and spreads, and fish. Furthermore, they said that several countries recommend supplementation to the general population – but added that recommended levels vary widely.
Indeed, Soininen and colleagues said that in most cases a daily supplementation of between 5 and 50 µg per day (corresponding to 200-2000 IU per day) is recommended – depending on age group and other factors.
The study was part of the Physical Activity and Nutrition in Children (PANIC) Study – a lifestyle intervention study at the Institute of Biomedicine at the University of Eastern Finland.
A total of 512 children aged 6 to 8 years participated in the baseline measurements in 2007–2009, constituting a representative sample of their age group.
The Finnish authors reported that children with blood levels of vitamin D, as measured by 25-hydroxyvitamin D, above 80 nmol/l had lower plasma total and low-density LDL cholesterol levels than children whose serum 25-hydroxyvitamin D levels were below 50 nmol/l – which is often regarded as a threshold value for vitamin D sufficiency.
Indeed, Soininen and her team found that serum 25(OH)D was negatively associated with total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides – even when adjusted for age and gender.
They said further studies are now needed to help detect the mechanisms for the associations found.
Source: Journal of Clinical Endocrinology and Metabolism
Published online ahead of print, doi: 10.1210/jc.2018-00335.
“Serum 25-hydroxyvitamin D, Plasma Lipids, and Associated Gene Variants in Prepubertal Children.” Authors: Soininen S