A person on a 20-year vegan eating regimen was hospitalized after his arm went numb for 4 days and he experienced troubled speaking.

The peculiar medical case of the 39-year-old man was published within the Cureus Journal of Medical Science. The report noted that the unnamed man had ‘undetectable’ vitamin B12 levels on account of his ‘strict’ vegan eating regimen.

Vitamin B12, also called cobalamin, is a naturally occurring nutrient present in meat, eggs, and dairy products. Deficiency on account of vitamin B12, which can be available in supplements, can severely damage the nervous system because it is important for nerves and oxygen-carrying red blood cells. The damage to the nervous system can develop into irreversible if left untreated for greater than six months after symptom onset, based on Insider.

“Although severe vitamin B12 deficiency is rare in america, recent increases within the adoption of vegan lifestyles have led to a big rise within the rates of B12 deficiency,” doctors wrote within the report.

The person sought medical attention when he felt ‘pins and needles’ in his arms together with numbness for 4 days. He also witnessed problem in speaking and shortness of breath, the doctors added. Other symptoms included intermittently blurry vision, lightheadedness, and lethargy.

Following evaluation, it was found that the person had near-zero vitamin B12 levels in addition to very low levels of red and white blood cells and platelets.

Those that have not consumed eggs, dairy, and meat for greater than five years are vulnerable to vitamin B12 deficiency, based on the British Dietetic Association. The agency further call on long-term vegetarians and vegans to often get their vitamin B12 levels checked and complement their eating regimen with around 10 micrograms per day of vitamin B12.

The person was treated with three blood transfusions and each day vitamin B12 injections for 2 days. His vitamin B12 injection dosage was regularly reduced with regular injections for five days at home, followed by an injection every week for 4 weeks, and eventually once a month.

The person showed drastic improvement after his treatment began. After just sooner or later of treatment, the person’s word-finding problems improved, and in two days, his coordination, tiredness, and breathlessness ameliorated. After one month of treatment, his confusion was “completely higher,” but there was still some numbness in his left hand, the doctors said.

“This case highlights the importance of taking a radical history, including dietary habits, when hematologic and neurologic symptoms may indicate a vitamin deficiency. It also highlights the importance of vitamin B12 supplementation for patients following a strict vegan or vegetarian eating regimen,” doctors concluded within the report.

Despite this grave medical case, veganism does have an edge over a non-vegetarian eating regimen, based on a separate study.

“Vegan diets have been linked to the reduction of risk for multiple chronic health conditions related to heart disease, type 2 diabetes, certain forms of cancer, and obesity. Resulting from its potential disease prevention links, it will not be surprising that vegans may live longer, as following a vegan eating regimen is linked to reduced occurrence of chronic disease. Nevertheless, more research is required to definitively conclude that vegans live longer than non-vegans,” Brooke Jacob, a registered dietitian at ChristianaCare, said.