How do your vitamins stack up?

B12, Folic Acid (Folate) and Vitamin D

Three vitamins that are especially important to physical and mental health are B12, folic acid, and D.

Adequate intake can be a challenge made more difficult by aging, drug interactions, smoking, drinking, body fat percentage, vegan and vegetarian lifestyles, conditions or procedures affecting the digestive system, and diets lacking in a variety of fresh fish, meats, vegetables, fruits, and legumes.

Vitamin B12

Vitamin B12, also known as cobalamin, is an essential vitamin produced by bacteria using cobalt. Humans depend on animal sources for B12. B12 is absorbed in animals then stored in muscle and organ tissue or passed to eggs and milk. Vegans are especially vulnerable to B12 deficiency because plants only have trace amounts. Vegan-friendly algae alternatives like Nori and Chlorella do contain suitable B12 stores and are being researched for bioavailability and efficacy.

B12 Sources:

B12 is naturally occurring in meat, fish, poultry, and dairy products. Foods rich in B12 include cooked clams, trout, liver and kidney meat. Oral B12 supplements are safe and effective for improving B12 levels. In fact, oral B12 supplements are significantly more affordable and found to be as safe and effective as B12 injections.*

Reference: Kolber MR, Houle SK. Oral vitamin B12: a cost-effective alternative. Can Fam Physician. 2014;60(2):111–112.

Optimal B12 Function and Benefit:

  • Energy: B12 is critical to producing healthy red blood cells that supply oxygen needed by every cell in the body
  • Metabolism: B12 is a necessary cofactor in a process that leads to efficient breakdown of fats and proteins into energy.
  • Healthy Aging: B12 is essential to DNA and cellular health which influence healthy aging. Low vitamin B12 status is highly prevalent in older age and is much more common than generally perceived. There is a wealth of epidemiological evidence to suggest that optimal vitamin B12 status is important for healthy aging and that low status is associated with an increased risk of chronic diseases of aging including CVD, dementia, cognitive impairment and osteoporosis.*

*Reference: Hughes, C. F., Ward, M., Hoey, L., & McNulty, H. (2013). Vitamin B12 and ageing: current issues and interaction with folate. Annals of Clinical Biochemistry, 50(4), 315–329.

Know Your B12 Range



Conditionally low


<150 ng/mL

<180 ng/mL

<400 ng/mL

>450 ng/mL

*Reference: McBride J. B12 Deficiency May Be More Widespread Than Thought [news release]. 2 Aug 2000. Washington DC, USDA Agricultural Research Service. Accessed 19 Feb 2019

Deficiency Symptoms:

Confusion and memory problems, fatigue and weakness, tingling or numbness, trouble with balance and walking, anemia

Who is at risk of deficiency?

Older adults, vegans and vegetarians, diabetics, celiac and Crohn's disease, gastric bypass surgery, those breastfeeding, individuals with excessive alcohol intake

Folic Acid (Folate)

Folic acid is a synthetic form of the essential vitamin folate. It is difficult to get adequate folate intake from food alone. Adequate folic acid (folate) is paramount to mental and physical health. Folic acid is especially important if you can get pregnant or are pregnant because it reduces neural tube birth defects, may support full-term birth and is associated with a lower incidence of autism. Folic acid supplementation is recommended by the CDC, World Health Organization, American Academy of Family Physicians, National Institutes of Health, and at least 20 European countries. Folic acid is cost-effective to produce, stable, and superior in terms of bioavailability and efficacy to dietary folate.

Folic Acid (folate) Sources:

Folate, derived from the word foliage, is naturally abundant in green leafy vegetables. Other foods high in folate include beef liver, Brussels sprouts, and avocado. Folic acid is added to bread, flour, pasta, rice, breakfast cereals, and corn masa flour.

Folic acid supplements are widely produced and commonly incorporated into multivitamins. Folic acid consumption should not exceed 1000 mcg per day without supervision from a doctor. A less common and more expensive form known as Methylfolate is also available as a supplement. Methylfolate may be more appropriate for certain individuals with a genetic variance known as C677T. Methylfolate may be recommended for individuals who have a history of neural tube defects in their family.

Optimal Folic Acid Function and Benefit:

  • Energy: Folic acid (folate) like B12 is critical to producing healthy red blood cells that supply oxygen needed by every cell in the body
  • Growth and Development: Folic acid (folate) helps in the production and repair of DNA and RNA especially when cells and tissues are growing rapidly such as infancy, adolescence and pregnancy. Folic acid (folate) is important in processes that drive gene expression and cell differentiation. Cell differentiation is an essential process for the development, growth, reproduction, and longevity of all multicellular organisms.
  • Mood and Cognitive Function: Adequate folic acid helps protect nerve cells and produce neurotransmitters. Low folic acid (folate) has been linked to cognitive decline, alzheimer’s, dementia, and depression. There is evidence that folic acid (folate) supplementation reduces homocysteine, decreases cytokine inflammation, slows cognitive decline in high risk patients, and improves symptoms of depression when added to certain treatments. Additional clinical trials are needed to better understand the effects of folic acid supplementation on cognitive function, cognitive decline, and depression.

Know Your Folic Acid (Folate) Range





<3 ng/mL

3.4  to 5.4 ng/mL

>5.4 ng/mL

5.4 to 19 ng/mL*

Reference: Sanchez, Hugo et al. “High levels of circulating folate concentrations are associated with DNA methylation of tumor suppressor and repair genes p16, MLH1, and MGMT in elderly Chileans.” Clinical epigenetics vol. 9 74. 24 Jul. 2017, doi:10.1186/s13148-017-0374-y

Deficiency Symptoms:

Irritability, shortness of breath, anemia, weakness and fatigue, depression, difficulty thinking

Who is at risk?

Older adults, diets lacking fresh fruits and vegetables, pregnant and lactating women, individuals with intestinal problems, those who smoke, hemodialysis patients, cancer patients, those with excessive alcohol intake

Vitamin D

Vitamin D research traditionally focused on its role to treat rickets and avoid weak bones. More recently with the discovery of vitamin D receptors throughout the body, a closer look at the role of vitamin D in chronic disease has revealed links to various health problems, including cognitive decline, depression, osteoporosis, cardiovascular disease, hypertension, diabetes, and cancer.

High doses of vitamin D can have health risks including kidney stones and cardiovascular damage due to elevated calcium in blood. A serum 25(OH)D concentration consistently >200 ng/mL is considered potentially toxic and most reports suggest a toxicity threshold for vitamin D of 10,000 to 40,000 IU/Day. The Society of Endocrinology suggests individuals older than 8 years of age not exceed 4000 IU of vitamin D without medical supervision.

Vitamin D Sources:

Human skin can make ample amounts of vitamin D when sufficient skin is exposed to sun. This can be from 15 minutes of sun in the afternoon for people with lighter skin or as much as two hours for people with darker skin.

Natural dietary sources of vitamin D include beef liver, egg yolks, oysters, tuna, mackerel, salmon, and some fish oil. Vitamin D is also fortified into dairy products, orange juice, soy milk, and cereals. Vitamin D supplements are common, safe, and effective for treating vitamin D deficiency.

Optimal Vitamin D Function and Benefit:

  • Healthy Bones and Muscle Strength: Vitamin D helps absorb calcium in the gut and reclaim calcium from the blood essential to build and maintain healthy bones and teeth. Vitamin D may also increase muscle strength which in turn helps prevent falls.
  • Support Immune System: Vitamin D exerts anti-inflammatory, anti-viral, antifungal, and antibacterial effects on immune cells. Vitamin D activates the repair process of damaged immune cells to ensure they stay in the fight. Vitamin D is an important immune system regulator shown to inhibit the development of autoimmune diseases. Vitamin D deficiency has been shown to increase susceptibility to infection. One well designed study demonstrated vitamin D supplements produced significant preventative effect against influenza A in school children during the winter.*

*Reference: Mitsuyoshi Urashima, Takaaki Segawa, Minoru Okazaki, Mana Kurihara, Yasuyuki Wada, Hiroyuki Ida, Randomized trial of vitamin D supplementation to prevent seasonal influenza A in schoolchildren, The American Journal of Clinical Nutrition, Volume 91, Issue 5, May 2010, Pages 1255–1260, https://doi.org/10.3945/ajcn.2009.29094

  • Energy: Vitamin D promotes the production of energy within the mitochondria that supports muscle function.

Know Your Vitamin D Range (The Endocrine Society, 2011)



Optimal All end points*

Optimal for cancer prevention*

<20 ng/mL

21 to 29 ng/mL

>30 ng/mL

36 to 48 ng/mL

Reference: Bischoff-Ferrari H.A. (2008) Optimal Serum 25-Hydroxyvitamin D Levels for Multiple Health Outcomes. In: Reichrath J. (eds) Sunlight, Vitamin D and Skin Cancer. Advances in Experimental Medicine and Biology, vol 624. Springer, New York, NY

Deficiency Symptoms:

Weak and brittle bones, frequent sickness and infection, fatigue and tiredness, insomnia, impaired wound healing, hair loss

Who is at risk?

Older adults, vegans and vegetarians, individuals with darker skin, those who consume less dairy, those lacking sun exposure, those with darker skin, individuals with higher body fat percentage, those with digestive problems

Take Home Point:

B12, Folic Acid, and vitamin D are vital to physical and mental health. They are also measurable within the body. Based on certain risk factors, or symptoms, your healthcare provider may order a simple blood test to assess these levels. Results put your finger on the pulse of your health. Addressing deficiencies and optimizing these three nutrients support better health and elevate your overall wellness.