Vitamin D deficiency can lead to obesity
We have now one more reason to maintain vitamin D in our body as researchers have found that vitamin D deficiency during early development can disrupt the metabolic balance between growth and fat accumulation.
Using a zebrafish model, the study, published in the journal Scientific Reports, suggests a linkage between vitamin D and metabolic homeostasis, or equilibrium.
"The vitamin D deficient zebrafish exhibited both hypertrophy and hyperplasia - an increase in both the size and number of fat cells," said study author Seth Kullman from the North Carolina State University in the US.
"They also had higher triglycerides and cholesterol, which are hallmarks of metabolic imbalance that can lead to cardio-metabolic disease," Kullman added.
This, combined with stunted growth, indicates that vitamin D plays an important role in the ability to channel energy into growth versus into fat storage.
For the study, the research team looked at groups of post-juvenile zebrafish on one of three diets: no vitamin D (or vitamin D null), vitamin D enriched and control.
The zebrafish spent four months on their particular diet, then the researchers looked at their growth, bone density, triglyceride, lipid, cholesterol and vitamin D levels.
They also examined key metabolic pathways associated with fat production, storage and mobilization and growth promotion.
The zebrafish in the vitamin D deficient group were, on average, 50 per cent smaller than those in the other two groups, and they had significantly more fat reserves.
After the initial testing, the vitamin D deficient zebrafish were given a vitamin D enriched diet for an additional six months, to see if the results could be reversed.
While the fish did continue to grow and begin to utilize fat reserves, they never caught up in size with the other cohorts and they retained residual fat deposits.
"This work shows that vitamin D deficiency can influence metabolic health by disrupting the normal balance between growth and fat accumulation," Kullman said.
"Somehow the energy that should be going toward growth is getting shunted into creating fat and lipids, and this occurrence cannot be easily reversed," Kullman added.
Future work will involve looking at the offspring of vitamin D deficient mothers, to determine whether this vitamin deficiency has epigenetic effects that can be passed down, the researchers noted.