Around one-quarter of people may be deficient in vitamin B12, research finds.
White spots appearing on the skin can be a sign of vitamin B12 deficiency.
The spots are often found on the outside of the forearm, although they may be in other places as well.
Over time these can become flaky and expose raw spots of flesh.
The reason vitamin B12 can cause these spots is because it can lead to low melatonin.
When melatonin is absent in the area, the white spots are left.
Other, more common signs of vitamin B12 deficiency include feeling tired, experiencing muscle weakness and being constipated.
Vitamin B12 can either be obtained from the diet or by supplementation.
Foods that contain high levels of vitamin B12 include dairy, liver, salmon and eggs.
For the study, 1,079 adults in Germany had their vitamin B12 levels measured.
More than one-quarter were deficient in vitamin B12, the results showed.
More than half were also deficient in vitamin D.
Ms Romy Conzade, the study’s first author, said:
“The results are very clear.
Fifty-two percent of the examined older adults had vitamin D levels below 50 nmol/L and thus had a suboptimal vitamin D status.”
The body uses vitamin B12 to make red blood cells and to keep the nervous system healthy.
Dr. Barbara Thorand, study co-author, said:
“Our study also shows that regular intake of vitamin-containing supplements goes along with improved levels of the respective vitamins.
However, vitamin-containing supplements are not a universal remedy, and particularly older people should watch out for maintaining a healthy and nutritious diet.”
The study was published in the journal Nutrients (Conzade et al., 2017).