Have you been feeling fatigued? It could be stress or sleeplessness, but for many people the cause of ongoing exhaustion is a vitamin deficiency. Though modern diets are fortified with key nutrients and supplements are popular, failure to consume a balanced diet can still result in nutritional shortfalls. In fact, trendy diets such as juice cleanses that billed as nutritionally optimal can be even worse in terms of vitamin balance than a more traditional meal plan.

If you’re struggling with a high level of fatigue, assess your diet for a shortage of these 3 vitamins. Among the most common causes of fatigue, adding more of these nutrients can help you feel more energetic.

Catch Some Rays: Vitamin D Deficiency

One of the most common vitamin deficiencies of the modern era is vitamin D, with shortfalls largely attributed to the fact that we spend more time indoors. Although you can take vitamin D supplements to boost your levels, you’re better off spending more time outside. Your body will synthesize more vitamin D if you spend 15 minutes out in the sun than by artificially introducing it to your diet. Just don’t forget to put on sunscreen before you head out.

All The Rage: Vitamin B12

It’s not surprising that vitamin B12 deficiencies are common – it’s one of the vitamins that our bodies can’t make independently. We have to consume it as a supplement or part of our diets. But more than other vitamins, B12 is given a great deal of credit for maintaining our energy levels, which has led to some health centers offering B12 shots to reduce fatigue, and many athletes swear by them. Such shots can be a great pick me up, but consider them a temporary solution rather than a long term nutrition management plan.

An Unusual Case: Vitamin C Deficiency

Vitamin C deficiencies are uncommon today, but you may be familiar with the term for such deficiencies in the past: scurvy. Scurvy was common in the 17th century among sailors who didn’t have access to fresh produce during long trips, but access to fruit and the addition of ascorbic acid to many foods has largely eliminated it. Even eating a few packets of ketchup each day would provide enough vitamin C to prevent scurvy.

Recently, however, doctors have started seeing more cases of scurvy among people with mental illnesses or who are living in poverty. Those with psychiatric conditions many opt for highly limited food choices due to their compromised mental condition or because of chronic unemployment, while those with little income are more likely to live in food deserts where fresh produce is expensive and hard to come by. The resulting fatigue is often mistaken for a symptom of mental illness or a stressful living situation, but is actually a symptom of scurvy.

Vitamin deficiencies happen to people from all walks of life, so it’s important to assess your diet to determine whether your fatigue stems from what you eat, rather than other lifestyle choices or health problems. Better food choices and a few supplements can have you feeling better in no time.