B-Complex Vitamins Use and Benefits
Written by TYE Medical on Oct 13th 2025
B-complex vitamins benefit your health in many ways, and if you don’t get enough B vitamins through your diet, supplements can help you reap the benefits. If you are a vegan, pregnant, or have certain medical conditions, you could benefit from adding B vitamins to your supplement regimen. There are 8 types of B vitamins found in many varieties of food, making it easy for most people to get what they need through diet alone.
But sourcing B vitamins through food only doesn’t work for everyone, because some people need more of these vitamins if certain factors apply such as:
- Pregnancy
- Age
- Diet
- Genetics
- Medical conditions
- Medications
- Alcohol use
If any of these factors affect you, you may benefit from vitamin B supplements. If you decide you need all 8 B vitamins, consider taking a B complex supplement that contains all of them. Otherwise, you can supplement individual B vitamins based on what you are most likely lacking. Meanwhile, here is more information about the health benefits, potential side effects, and benefits of B-complex vitamins.
What Are B-Complex Vitamins?

B-complex vitamins condense all 8 B vitamins into one pill. Since they are water soluble, your body flushes out excess levels of the vitamins instead of storing them. This is a benefit, because too much of a vitamin stored in your body can be damaging. You don’t have to worry about overdosing on B vitamins and can take a reasonable dose daily.
What will you find contained inside a B-complex supplement? A B-complex pill usually contains the following:
- B1 (thiamin) - vital for metabolism and converting nutrients to energy. Plentiful in sunflower seeds, pork, and wheat germ.
- B2 (riboflavin) - acts as an antioxidant and converts food to energy. Notably found in beef, mushrooms, and organ meats.
- B3 (niacin) - Niacin is important for metabolism, DNA production and repair, and cellular signaling. Good sources are lentils, chicken, and tuna.
- B5 (pantothenic acid) - helps derive energy from food and helps produce hormones and cholesterol. Found plentifully in fish, liver, avocado, and yogurt.
- B6 (pyridoxine) - assists in producing red blood cells, creating neurotransmitters, and metabolizing amino acids. Good sources are salmon, potatoes, and chickpeas.
- B7 (biotin) - metabolizes fat and carbohydrates, regulates gene expression. Notably found in cheese, liver, salmon, eggs, and yeast.
- B9 (folate) - forms red and white blood cells, assists in proper cell division, metabolizes amino acids, assists in cell growth. Good sources include liver, beans, greens, or folic acid supplements.
- B12 (cobalamin) - crucial for neurological function, red blood cell development, DNA production. Rich sources are eggs, meat, dairy, and seafood.
Each of these B vitamins impact your health in important ways and should be consumed in varying amounts daily. How you supplement, whether individually or with a complex vitamin depends on where you seem to be lacking the most in your diet and what other factors might necessitate needing more than the usual intake.
Who Should Take a B-Vitamin Complex Supplement?

If you follow a well-rounded diet, you’re not likely to need a B-Complex vitamin. This is because B vitamins are readily available in many foods, so if you eat a healthy variety of whole foods, you’re probably getting what you need.
But it’s not that easy for everyone. Some people require more B vitamins than the average person due to the following factors.
Take a B complex if you are pregnant or nursing
During pregnancy, your body is under increased demand for B vitamins like folate and B12. These vitamins are needed to support the developing baby. B Complex supplementation is vital especially if you are vegetarian or vegan while pregnant. If you are deficient in folate or B12 while pregnant or nursing, the infant may experience neurological damage or birth defects.
Take a B complex if you are an older adult
Age diminishes your body’s ability to absorb B12 and your appetite naturally declines so that you’re not eating enough B12 containing foods as previously. It’s not uncommon for older adults to develop vitamin B12 deficiency. You require an adequate amount of stomach acid release B12 from food for absorption, but many older adults don’t produce the stomach acid in the necessary amounts. This is especially true if you are treating acid reflux or heartburn with acid-reducing medication, which interferes with B12 absorption.
Take a B complex if you have certain medical conditions
You are more likely to develop B vitamin deficiencies if you have health conditions like:
- Crohn's disease
- Celiac disease
- Hypothyroidism
- Alcoholism
- Anorexia
Doctors often recommend that you supplement with a B vitamin complex if you have any of these medical conditions.
Take a B complex if you are a vegetarian or vegan
B12 exists naturally in animal products like dairy, meat, seafood, and eggs, which really cuts out the best quality sources for vegans and vegetarians. If you cut out meat or animal products, it’s extremely easy to become B12 deficient and even low in some other B vitamins without supplementing. A B-complex vitamin is highly recommended to ensure you maintain nutrition and health.
Take a B complex if you take certain medications
Several common medications can lead to B vitamin deficiencies. Proton pump inhibitors taken to reduce stomach acid can also prevent the processing absorption of B vitamins, specifically B12. Additionally, Metformin, a very common and well-known, non-insulin medication used to treat diabetes, also reduces levels of both B12 and folate.
What Are the Health Benefits of B Vitamin Supplements?

Experts believe that B vitamin supplements are beneficial even if you aren’t otherwise at risk for deficiency. Here’s why…
B Vitamins Boost Mood and Reduce Stress
People often use B-complex vitamins to decrease fatigue and lift their mood. Some studies support the claim that B vitamins boost mood and even enhance cognitive abilities. Other studies indicate that you can get enough B vitamins to lift your mood by taking a multivitamin that contains high-levels of B vitamins. However, you must take the supplement for at least 90 days to see improvement in negative mood.
B Vitamins May Improve Symptoms of Anxiety or Depression
B vitamins cannot cure mental health conditions, but they can help reduce anxiety and depression symptoms. This is because a lack of B vitamins, especially B12, B6, and folate can increase your risk of depression. If you struggle with anxiety or depression, be sure to rule out vitamin and nutrient deficiencies as a source. You may want to consider other vitamins and nutrients that affect brain health.
What Is the Recommended Dosage for B Vitamin Supplements?

A recommended dosage exists for each B vitamin, so if you’re buying a B-complex supplement, consider how much of B vitamin it contains. The supplement and dosage you choose will also vary based on gender, age, other circumstances like pregnancy.
|
|
WOMEN |
MEN |
|
B1 (thiamine) |
1.1 mg |
1.2 mg |
|
B2 (riboflavin) |
1.1 mg |
1.3 mg |
|
B3 (niacin) |
14 mg |
16 mg |
|
B5 (pantothenic acid) |
5 mg |
5 mg |
|
B6 (pyridoxine) |
1.3 mg |
1.3 mg |
|
B7 (biotin) |
30 mcg |
30 mcg |
|
B9 (folate) |
400 mcg |
400 mcg |
|
B12 (cobalamin) |
2.4 mcg |
2.4 mcg |
Keep in mind that these are the recommended daily dosages, but if you are deficient, you may need to take higher doses to correct the deficiency. It can be helpful to talk with your doctor about your nutrients needs, considering both your age and health.
What Are the Possible Side Effects of B Vitamin Supplements?

Remember that you don’t have to worry about consuming too much of a B vitamin, because they are a water-soluble nutrient that is regularly flushed from your body. However, if you take an excessively high dosage of a B vitamin, you could experience some serious side effects.
For example, high doses of B3 (niacin) can cause high blood sugar levels, vomiting, skin flushing, and liver damage. High doses of B6 can cause nerve damage, painful skin lesions, and light sensitivity.
Also be aware that a benign side effect of B vitamins is bright yellow urine. When you see this, don’t be alarmed, as it is completely harmless. It’s simply your body ridding itself of excess vitamins.
It’s best to choose a vitamin brand that chooses to have their products independently tested by places like the US Pharmacopeia (USP). This provides accountability for its contents since vitamins and supplements aren’t regulated by the Food and Drug Administration (FDA).
Recap of B-Complex Vitamin Uses and Benefits

While anyone can benefit from taking a B-complex vitamin, if you’re pregnant, an older adult, or vegan (vegetarian), it’s highly recommended to prevent B vitamin deficiencies. If you aren’t likely to be deficient based on these factors, then consider talking with your doctor to determine your individual nutritional needs.
Benefits of B-complex vitamins included boosting mood, improving depression symptoms, enhanced energy, and reduced stress. Often the benefits outweigh the side effects, especially since complications only arise if you far exceed the recommended dosage. Otherwise, it’s perfectly safe to take proper dosage daily, even if your body doesn’t use all of it.
