The first week after the clocks change is always hard mentally. We’ve been seeing lots of jokes about the sun clocking out of work before us, and it’s hard not to find that a little depressing. It’s nice to wake up in sunlight again, but it is rough to have it be dark so early in the day. Sunlight can also mess with your blood sugar.
Exposure to sunlight is linked to lower blood sugar and a lower risk of blood sugar concerns. Researchers looked at data from more than 400,000 people in the UK Biobank. They found that short-term sunlight exposure was linked to reductions in blood glucose. Long-term sun exposure was linked to lower risks for serious blood sugar concerns.
The researchers compared blood glucose measurements to levels of ultraviolet A (UVA) radiation around the homes of the participants for seven days. They found that increasing exposure to UVA decreased blood glucose. However, it wasn’t a straight line. Blood sugar decreased the most when people went from very little sunlight to getting some light. Then it plateaued. The biggest impact of sunlight on blood sugar was seen in the winter. That makes sense, as it’s when light is hardest to come by. In spring, summer and fall, there may be too much sunlight to see “metabolic benefits.”
The researchers looked at sunbed use and blood sugar health. Occasional sunbed users had a 14 percent lower risk of developing a serious blood sugar concern. Frequent sunbed users had a 22 percent lower risk. They also had higher levels of vitamin D. However, sunbeds are also linked to skin cancers, including melanoma.
The researchers pointed out that nitric oxide is released into the body after UV exposure. Nitric oxide can improve blood flow, insulin secretion and sensitivity.
Several studies have found that lower levels of vitamin D are linked to a higher risk of serious blood sugar concerns. But studies have not found how low is too low or found enough support to recommend supplementing vitamin D.
“Light is an underestimated lifestyle factor when it comes to metabolism,” said Patrick Schrauwen, a senior scientist at the German Diabetes Center in Düsseldorf who has been studying this relationship. “We focus on diet and exercise, but I think exposure to natural light also plays a role.”
Now that the clocks have fallen back, try to get more light into your day by spending time outdoors and by windows. It could help your blood sugar as well as your mood.
