Vitamin B12 Deficiency: Signs, Symptoms, and Brain Health Impacts
Do you tend to avoid eating clams, salmon, or eggs? Are you taking medications for type 2 diabetes? If so, you may be among the up to 40% of people aged 60 and older who are deficient in vitamin B12.1 Your diet plays a significant role in maintaining vitamin B12 levels, and other factors may also contribute to a B12 status. Your body often sends out warning signals when B12 levels drop, and it’s crucial to pay attention and watch out for these to know when you need to address a vitamin B12 deficiency. Keeping your B12 levels optimal is an important piece for supporting your energy levels, mood, and your short and long-term brain health.
Keep reading to learn what vitamin B12 is, why you may find yourself with low levels, the signs of a B12 deficiency, and some effective strategies to help boost your vitamin B12 intake.
What is Vitamin B12
Vitamin B12, also known as cobalamin, is a water-soluble vitamin found in animal products like fatty fish, seafood, red meats, dairy, and eggs. B12 is not typically found in plant-based foods, although some foods like cereal are fortified with B12, meaning it’s added to them. Vitamin B12 is an extremely important nutrient because it acts as a helper for enzymes that help your body create DNA and red blood cells, controls homocysteine levels (which are linked to heart and brain health), and helps your brain function properly.2
It's easy to see why avoiding a vitamin B12 deficiency is so important for your overall health. Next, we'll explore the signs and symptoms of a B12 deficiency to look out for.
Signs and Symptoms Your B12 Levels are Low
It can be difficult to know if your vitamin B12 levels are low without getting tested, as many people experience subtle symptoms that can easily be overlooked. However, paying attention to certain warning signs can help you recognize if your body may be signaling low levels or a deficiency.
Some symptoms you can look out for include:3
- Low energy
- Headaches
- Depression
- Muscle cramps
- Brain fog
A vitamin B12 deficiency is typically indicated by blood test results below 160 picograms per milliliter (pg/mL) or 118 picomoles per liter (pmol/L). However, it’s important to note that the "normal range" for B12 is really wide, spanning from 160 to 950 pg/mL (118 to 701 pmol/L). While a result of 160 pg/mL may suggest deficiency, levels that fall within the normal range can still be suboptimal for long-term health. Therefore, when discussing B12 deficiency, it's crucial to consider not just the deficiency status but also the potential for suboptimal levels. Everyone is different, and B12 has a particularly wide range, which could also indicate a wide range of when suboptimal and deficient status occurs.4
Why You Might Be Deficient in Vitamin B12
Your Diet: First and foremost, your diet plays a central role in your vitamin B12 levels. If you're vegetarian or vegan or you don’t typically eat seafood, red meat, or other animal products, you’re more likely to be at risk of B12 deficiency.5
Old Age: As we get older, the body’s ability to absorb B12 becomes less efficient. The process is complex, involving the stomach, pancreas, and small intestine, and having to do with intrinsic factor and not having enough in our stomachs as we age. Specifically with age, factors like reduced stomach acid or certain health conditions can hinder proper B12 absorption, making it harder for older adults to maintain adequate levels, even with a balanced diet.6
Medical Conditions: It's important to assess any medical conditions that could be a hidden cause of a vitamin b12 deficiency. One such condition is cobalamin-deficiency anemia, commonly known as pernicious anemia. Pernicious anemia is an autoimmune disease that affects the stomach lining and can lead to a condition called gastric atrophy, where the stomach loses its ability to function properly. This disease attacks the parietal cells in the stomach, which are responsible for producing intrinsic factor—a protein that is essential for absorbing vitamin B12. As a result, people with pernicious anemia cannot properly absorb dietary vitamin B12, even if they consume enough through their diet.5
Another condition to consider is Crohn's disease, an inflammatory condition that affects the gastrointestinal (GI) tract. It often impacts the terminal ileum, the part of the intestine responsible for absorbing B12, making it difficult for individuals with this disease to maintain healthy B12 levels and often facing a B12 deficiency.7
Celiac disease can also lead to a vitamin B12 deficiency. In this condition, the body's immune response to gluten damages the lining of the small intestine, affecting nutrient absorption. Iron and folate malabsorption are common in untreated celiac disease, further complicating nutritional health, in conjunction with low vitamin B12 levels.8
Medications: Certain medications you take can also affect your vitamin B12 levels. For instance, semaglutide, commonly known as Ozempic, is a newer drug used primarily for managing type 2 diabetes and weight loss. Early studies suggest that it may lower B12 levels, but more research is needed since it is quite new on the market.9
Metformin, another medication used to treat type 2 diabetes, has been shown to impact vitamin B12 absorption. Some research suggests that metformin may disrupt the absorption of vitamin B12 in the ileum, the (previously mentioned) part of the intestine responsible for taking in this crucial vitamin. Normally, vitamin B12 absorption relies on a complex with intrinsic factor, which requires adequate calcium levels in the intestines. Metformin may affect this process by altering the surface charge of intestinal membranes, potentially making it harder for calcium to assist in vitamin B12 absorption.10
Vitamin B12 Deficiency Impact on Your Brain Health
Vitamin B12 is vital for regulating homocysteine levels, an amino acid that, in high concentrations, can be harmful and is associated with an increased risk of cognitive decline. When B12 levels are low, homocysteine can rise, leading to silent brain injury from oxidative stress. Individuals with Alzheimer’s disease often have lower B12 levels and higher homocysteine. Research shows a strong link between elevated homocysteine and cognitive decline, particularly affecting executive functions and resulting in memory problems, poor focus, and lethargy.11
Levels You Should Aim For
The need for vitamin B12 can vary significantly from person to person based on individual circumstances and health conditions. Generally, the recommended daily intake is 2.4 micrograms each day for both males and females.5 This can be 3 ounces of clams or fish like salmon, or one large egg. However, individuals with pernicious anemia, older persons, or those who have difficulty absorbing vitamin B12 may require higher intakes through their diet, and sometimes they must even administered B12 through injections.12 Consult with your healthcare professional to determine the appropriate dosage for your specific situation.
How to Increase Your B12 Levels
Now that you have a clearer understanding of the factors that can contribute to vitamin B12 deficiency and some common signs to watch for, it's time to explore effective ways to boost your B12 levels.
- When it comes to maintaining a brain-healthy diet while addressing your vitamin B12 levels, incorporating more fatty fish and seafood is highly recommended. Shellfish like clams, oysters, and mussels are especially rich in B12, making them excellent choices for boosting your intake. While red meat is also a good source of vitamin B12, it's generally not advised in a brain-healthy diet due to its higher fat content. If you're a vegetarian or vegan, a great alternative is to sprinkle nutritional yeast on your meals, providing an easy and effective way to add more B12 to your diet.5
- Incorporating more probiotics into your diet can be a great approach to boosting your vitamin B12 levels. The bacteria in our intestines play a key role in producing (and consuming) vitamin B12. Although our scientific understanding of it is still in the early stages, research is indicating that certain probiotics have been shown to produce B12 and may help improve its absorption in the gastrointestinal tract. By taking probiotics, you can help balance these bacteria, promoting those that support B12 production while inhibiting those that consume it.13
- Eliminating or reducing your alcohol intake can help in maintaining healthy vitamin B12 levels. Studies have shown that excessive alcohol consumption can lead to lower B12 levels in the body, potentially due to its negative impact on absorption and liver function. By eliminating or reducing your alcohol intake, you can help ensure your body is better equipped to absorb important nutrients, including vitamin B12.14
- Taking a vitamin B12 supplement is one of the most direct ways to ensure your body and brain receive a sufficient daily dose of this nutrient. Consider choosing the hydroxocobalamin, methylcobalamin, or adenosylcobalamin forms of B12. These are believed to be converted into active forms (or are already active) more efficiently and (particularly for hydroxocobalamin) retained in the body for longer periods than the more common cyanocobalamin. This means that they may provide more effective support for your energy levels, cognitive function, and overall well-being.11
Our brain health supplement RELEVATE contains hydroxocobalamin (also referred to as hydroxycobalamin), a naturally occurring form of vitamin B12 that the body can flexibly convert into other active forms as needed. This type of B12 is the most abundant form in foods, especially in clams and mackerel, and it stays in the blood longer, helping to build your B12 stores. RELEVATE’s hydroxycobalamin is designed to be easily absorbed, making it beneficial for individuals, including those with absorption challenges. Plus, research links this form of B12 to a reduction in cognitive decline, particularly as we age.15 Along with 16 other brain health nutrients, RELEVATE provides support for short and long-term brain health in an easy daily routine. You can learn more about it by visiting here.
Vitamin B12 is vital for our bodies to function optimally, playing a crucial role in everything from brain health to energy production. By staying vigilant for the signs of a vitamin B12 deficiency and understanding the potential causes, you can take proactive steps to support wellness for your brain (and beyond) for the long-run.
Do you want to learn more about B12. Click below for other articles and topics we’ve covered on B12.
Exploring B-Vitamins: Forms, Functions, Choices for Brain Health, and More
11 Top Nutrients & 3 Smart Choices for the Gut-Brain Axis
Top 13 Nutrients to Supplement for Long Term Brain Health and Memory
Are You Vitamin Deficient? Here are Causes and Their Health Impact
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