The days are shorter, you’re hibernating inside — and there’s a good chance you’re not getting enough vitamin D.
About 40% of Americans aren’t. But in case you’re waiting for a sign from your body to pick up a supplement, an expert has broken down the symptoms that may spell danger for your vitamin D levels.
Stephanie Schiff, a registered dietitian nutritionist at Northwell Huntington Hospital, tells The Post that even if you’re a serious sunbather, you’re unlikely getting what you need simply by soaking up some rays.
“If you’re going out for any period of time during the day, even if you’re taking all your clothes off, you’re probably not getting enough vitamin D from the sun,” she said.
In fact, she said most people she knows of have too-low levels of vitamin D — and unfortunately, it’s incredibly tricky to tell without a blood test.
“It’s really hard to pinpoint a lack of vitamin D,” she said.
Typically, by the time a lack of it is presenting itself in your body, you’ve been deficient for a while — and in that case, these are the signs screaming “get some more D now.”
Bone and joint pain
“The problem with not getting enough vitamin D is you really need it to help your body to absorb calcium and phosphorus,” Schiff explained.
Without it, you can develop osteomalacia, which is a softening of your bones. That can be painful and also lead to more frequent breaks and fractures, so if you’re finding yourself in casts more often, that can be a clue.
Muscle weakness, pain and spasms
Schiff said muscle pain that feels similar to growing pains can be a sign of a vitamin D deficiency, as can something called hypocalcemic tetany, which is the random twitching of muscles.
This is a hard one to spot, since muscle twitching can have lots of other causes, including dehydration.
Teeth problems
When that lack of vitamin D leads to less calcium being absorbed, that can mean issues with all your bones — including the ones in your mouth.
If you’re getting lots of cavities — especially if you haven’t in the past — that could be your teeth telling you to get more vitamin D, stat.
You may experience other dental problems, too, like gum disease and gingivitis.
Hair loss
Low vitamin D has been linked to several different types of hair loss, including telogen effluvium (stress-related hair loss), androgenetic alopecia (pattern hair loss) and alopecia areata (patchy hair loss).
If your find that your hair is thinning, it can be worth checking to see if low vitamin D levels are to blame.
Interestingly, a 2020 study found an association between vitamin D deficiency and trichotillomania, the disorder in which people pull out their hair, sometimes including eyelashes.
Can’t eat, can’t sleep
Low vitamin D can make you tired — though as Schiff points out, so can an endless number of other things.
But it can also make it harder to sleep, since vitamin D plays a role in regulating melatonin, the hormone that controls our sleep cycles.
Research has also shown that vitamin D is involved in regulating leptin, the appetite regulating hormone, so not getting enough can mess with your hunger cues.
How do you increase your vitamin D levels?
The recommended daily allowance for adults is 600 IUs, or 800 IUs for people over age 70. You can simply take a supplement, but Schiff likes getting it through food as much as possible — even though that’s not that easy.
Fatty animal foods like beef, liver, fish, egg yolks, cheese and butter have it naturally, while some food products are fortified with more vitamin D, like breakfast cereals, plants, almond milk, soy milk and oat milk.
But if you’re going the supplement route, beware taking too much.
“I wouldn’t want anybody to take any more than the recommended daily allowance,” Schiff said. “With vitamin D, more is definitely not better. You can get to a level of excess vitamin D where there is toxicity.
“You’ll never get to the level from the sun, but that can happen with supplements or even eating too many vitamin D foods.”
Symptoms of vitamin D toxicity include nausea, weakness, excess urination and kidney issues.