Published on September 10, 2023

Vitamin B12 Supports Mood, Memory, Energy

Many seniors become deficient in this important nutrient.

B-12 Vitamin

Written by Melissa Bean Sterzick

Of the health concerns that increase with age, vitamin deficiencies can be some of the easiest to resolve. Vitamin B12 supports some of the body’s most important functions, including the health of the central nervous system, the creation of red blood cells and the synthesis of DNA. Those functions might seem obscure, but they all point to several important aspects of good health: memory, energy and mood. Torrance Memorial Physician Network’s Mona Madani, MD, recommends seniors keep track of their B12 levels with the help of their primary care physician.

Advantage: How is vitamin B12 important for good health?

Dr. Madani: Vitamin B12 supports some of the body’s most important functions. It helps with creating red blood cells, which support the transport of oxygen. It also prevents anemia. It is beneficial for increasing energy levels, as well as helping prevent memory loss. Vitamin B12 supports bone health—as we age, we have a greater risk of developing osteoporosis. And it’s good for mental health.

Why do seniors need to pay close attention to their vitamin B12 levels?

Complications can arise if you are deficient. Seniors should have normal B12 levels in order to help maintain cognition and prevent worsening mood and poor emotional health. It’s more common for seniors to have lower B12 levels. Changes in digestion that come with age decrease the body’s ability to absorb the vitamin. In addition, regular use of antacids and ulcer medications can inhibit B12 absorption.

What are the signs of a B12 deficiency?

Signs of a B12 deficiency include nerve pain, numbness or tingling in the extremities, fatigue and a decrease in energy. Cognitive decline, irritability and mood changes can also occur. Sometimes people experience weaker muscles and gait issues, which may include difficulty walking and problems with balance.

How is a B12 deficiency diagnosed?

The best option is a blood test—a CBC or a B12 level check. Your primary care physician can order this easily at your annual exam. Once a year is enough if you are not experiencing symptoms of deficiency. If you are starting treatment for B12 deficiency, we may check it more often.

What foods have a lot of this nutrient?

B12 is in foods such as meat and dairy, turkey, tuna and chicken. Breakfast cereals often have it, as well as spinach, eggs and bananas. Not many fruits and vegetables have B12. Vegans and vegetarians have a higher risk of deficiency. A history of irritable bowel syndrome can affect absorption. People who have had gastric surgeries may also have lower levels of B12.

Are supplements helpful?

Yes, typically B12 comes in oral tablets, liquid form and sublingual. Liquid and sublingual have higher efficacy. It’s very difficult to overdose because it’s a water-soluble vitamin. B12 shots (injection form) are very effective and may be administered once a month. For seniors, we also look at vitamin D, calcium, magnesium and potassium.

Dietitian-Approved Tips

Provided by the Torrance Memorial Dietitian Team

Vitamin B12 is a water-soluble vitamin. Aside from playing a role in red blood cell formation, it is also required for the development and function of the central nervous system.

Sources of vitamin B12:

  • B12 is found in all foods of animal origin, including meat, fish, poultry, eggs and dairy products, such as milk, yogurt, and cheese.

Vegetarian sources of B12 include:

  • Vitamin B12-fortified foods include fortified nutritional yeast, soy milk, meat substitutes and ready-to-eat cereals (be sure to check the label, as not all products on the market are fortified with vitamin B12).
  • Nutritional Yeast: A health supplement grown on molasses, sugar beets or wood pulp. May be used as a condiment or added to recipes to provide a cheese-like flavor.
  • Taking a B12 supplement may also be needed, but check with a health care provider first.

Groups at risk for vitamin B12 deficiency:

  • Older adults, individuals with pernicious anemia, gastrointestinal disorders or gastrointestinal surgery, vegetarians or vegans, or infants of women who are vegan.
  • Intake recommendations for vitamin B12 and other nutrients are provided in the Dietary Reference Intakes developed by the Food and Nutrition Board. Visit with a registered dietitian nutritionist today to learn more about your exact needs and how to follow a general, healthful diet.

If you have questions or are interested in learning more techniques to help build a healthy and nutritious lifestyle, contact one of our registered dietitian nutritionists at the Outpatient Medical Nutrition Therapy Office or our Diabetes Self-Management Program located in the Torrance Memorial Specialty Center, 2841 Lomita Blvd., Suite 335, Torrance. Call 310-891-6707. Visit TorranceMemorial.org/nutrition for upcoming classes and programs!


Mona Madani, MDDr. Madani is board-certified in family medicine with interests in preventive care, chronic disease management, women’s health and functional medicine. She enjoys working in a primary care clinic environment and is devoted to forming relationships with her patients, which is one of the reasons she chose family medicine. She strives to provide high-quality care to patients of all ages and promotes patient-centered care in her practice. 

Mona Madani, MD, practices at Torrance Memorial Physician Network Primary Care in El Segundo at 2110 E. El Segundo Blvd., Suite 200. She can be reached at 310-517-7030.