“By some estimates, up to 40 percent of the population does not have sufficient levels of B12,” Connealy writes.
The B vitamins work together as a family to perform many important functions throughout the body, such as helping to convert our food to fuel, allowing us to stay energized through the day, helping maintain heart health, preventing birth defects, creating red blood cells or assisting with the production and repair of DNA, to name a few.
Vitamin B12, or cobalamin, keeps our blood, nervous system and heart healthy. It is found primarily in animal-sourced foods—all meats, dairy products, eggs, and shellfish. Liver, sardines, and salmon contain the greatest amount.
Image from webmd.com
Absorption issues in younger people are often caused by acid-blocking medications, disorders such as Crohn’s disease, leaky gut, diarrhea and other gastrointestinal problems. Older people with a condition called hypocholorhydria, where the stomach does not produce enough acid to help with the absorption of nutrients, can have low levels as well, Connealy notes.
B12 deficiency can cause a wide variety of debilitating symptoms ranging from exhaustion and lethargy to depression, anxiety, memory loss, confusion, and other Alzheimer’s-like symptoms.
WebMD adds rapid heartbeat and breathing, pale skin, sore tongue, bleeding gums, stomach upset and weight loss and diarrhea or constipation to the list of symptoms.
Connealy notes that there are differing recommendations for the amount of B12 that should be in a supplement. The Dietary Reference Intake recommends between 2-3 micrograms daily, while the Center for Food Safety and Applied Nutrition recommends 6 mcg daily, based on a 2,000-calorie diet.
Connealy recommends the higher dosage, especially since “absorption problems are so common with age” and “it’s nearly impossible to overdose.” She also recommends B12 injections for severe deficiencies. In particular, she says that vegetarians, vegans and those age 50 and older should take an oral B12 supplement every day.