Often mentioned in history books and pirate tales, scurvy is hardly the subject of modern-day medicine. Documented as early at 1550 B.C. by Hippocrates and the Egyptians, the rare disease was most known for striking those who were away for long bouts at sea.

Early symptoms include fatigue and nausea but without treatment, the disease can progress to include bleeding gums, loose teeth and dark, scarred skin.

According to the Science History Institute, scurvy killed more than 2 million sailors between Columbus's voyage and the growth of steam engines in the mid-1800s. Scurvy was such a common problem that on any major voyage, it was expected that half of all sailors wouldn't survive.

Historian Stephen Bown says scurvy was responsible for more deaths at sea than storms, shipwrecks, combat and all other diseases combined. The hunt for a cure was what Bown describes as "a vital factor determining the destiny of nations."

Doctors eventually realized that the "scourge of the sea" was the result of a missing nutrient — namely vitamin C. When sailors were at sea, they had little access to fresh fruits and vegetables, which then wreaked havoc on their health.

Why is scurvy back?

fruits and vegetables Scurvy comes from a lack of vitamin C, which can be found in citrus fruits and some vegetables. (Photo: ratmaner/Shutterstock)

These days, we understand the importance of vitamins and minerals in our diets, but not everyone has access to fresh fruits and vegetables.

Between 2009 and 2014, hospital admissions in the United Kingdom related to scurvy went up by 27 percent.

Lucy Jackman, a pediatric dietitian and spokesperson for the British Dietetic Association, tells the BBC that even though we're aware of what constitutes healthy eating, low-income families and those dependent on drugs or alcohol are often most at risk.

She also sees a few children with vitamin C deficiency, which is generally related to "very fussy eating."

"The key is to catch it early, get the message across about balanced eating and to make sure they are eating five portions of fruit and vegetables every day."

Here in the United States, many people might seem to get enough to eat, but the food they're eating isn't rich in vitamins.

"We diagnosed our first case [of scurvy] about five to six years ago. The initial case came through the hospital and was quite dramatic, someone with a mental health issue who would only eat bread and cheese," Massachusetts-based Dr. Eric Churchill told ScienceAlert.

"Between then and now we have diagnosed somewhere between 20 and 30 cases of scurvy."

Churchill was featured in the documentary "Vitamania," a film made by popular scientist Derek Muller of YouTube fame that looks at vitamins, supplements and nutrition in foods.

When people are on a limited income, they might choose filling, inexpensive foods versus nutritious foods, resulting in health issues like scurvy.

Some scurvy cases have also popped up in Australia in recent years. In 2016, doctors noticed a resurgence of scurvy in a group of patients with diabetes in a Sydney hospital.

"When I asked about their diet, one person was eating little or no fresh fruit and vegetables, but the rest ate fair amounts of vegetables; they were simply over-cooking them, which destroys the vitamin C," professor Jenny Gunton, who heads the Diabetes Centre at the Westmead Institute for Medical Research, told the Australian Broadcasting Corporation.

"This result suggests that despite the large amounts of dietary advice readily available to the community, there are still plenty of people — from all walks of life — who are not getting the messages."

Mary Jo DiLonardo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.

Is scurvy making a comeback?
Scurvy is old disease that's coming back because not everyone knows about or can afford nutritious foods.