Disclaimer: This content has been produced purely for informational and educational purposes only and is never intended to be used as a substitute for professional medical guidelines including diagnosis, advice, and treatment. 

When we talk about vitamin D3 vs B12, the basic difference lies in their molecular structure, vitamin D3 is a fat-soluble vitamin whereas vitamin B12 is a water-soluble vitamin. But these vitamins are different from the other vitamins, they are lacking in plant sources, for instance, and the human body develops difficulty absorbing them gradually with aging.  

In this article, we’ll be discussing vitamin D3 vs B12 in terms of their properties, functions, and symptoms of deficiencies. But before we get into the difference between vitamin D3 and B12, it’s worth knowing the basics of them a little bit more. So, let’s get started. 

Table of contents 

• What is vitamin D3? 
• What is vitamin B12? 
• Vitamin D3 vs B12: properties and functions 
• Vitamin D3 vs B12: symptoms of deficiencies 
• Why you might need vitamin D3 and B12 supplements 

What is vitamin D3? 

Vitamin D3 is a fat-soluble vitamin that belongs to a group of vitamins called vitamin D that includes various other forms such as vitamin D1, D2, and D4. 

Vitamin D is best known for its contribution to building bones and keeping them strong, but it also benefits the immune system, brain, muscles, and digestive system. For this reason, low levels of it may cause muscle weakness that may increase the risk of falls, especially in older ages. 

The human body can make vitamin D in the presence of sunlight or get it from certain foods, particularly animal foods. Since sun exposure has a cancer risk and many people do not like animal foods all the while, it’s hard to reach the minimum requirement for it for most people, specifically vegan or vegetarian people. Hence, people turn to vitamin D supplements. Clinicians prefer vitamin D3 supplements over the other forms of vitamin D as it is more efficient and better absorbed.  

What is vitamin B12? 

Vitamin B12, also known as cobalamin, is a water-soluble vitamin that belongs to a group of vitamins called B vitamins. It’s one of eight B vitamins that include vitamin  B1 (thiamin), vitamin B2 (riboflavin), and vitamin B3 (niacin), and others. 

Vitamin B12 naturally occurs in various foods such as fish like tuna, sardines, salmon, trout, and shellfish, poultry and dairy products like eggs, yogurt, and cheese, and certain fortified foods like cereals. But it is lacking in plant foods and therefore, vegan people might want to consider vitamin B12 supplements.   

Vitamin D3 vs B12: properties and functions 

Vitamin D3 helps the human body more specifically the intestine to properly absorb a wide range of nutrients including vitamins and minerals such as calcium and phosphorus that are essential for a whole lot of biological functions in the body. Vitamin D3, in turn, ensures:  

• Proper growth and development of bones 
• Proper growth and development of muscles 
• Proper functioning of the endocrinology system 
• Proper functioning of the immunity system 
• The proper rhythm of the heart by enabling heart muscles to contract properly 
• Proper brain and cognitive functions 

Vitamin B12, on the other hand, assists a whole variety of enzymes to do their jobs. It helps break down foods such as protein and carbohydrates into their absorbable forms and plays a key role in transporting energy-containing nutrients and oxygen throughout the body. It has a noticeable positive effect on sleep and mental health, which is why it is commonly used, along with melatonin, to promote sleep and mental health. In addition, vitamin B12 is essential for: 

• Formation of DNA 
• Production of red blood cells 
• Proper development and functioning of the nervous system, especially brain and nerve cells 

Vitamin D3 vs B12: symptoms of deficiencies 

Symptoms of vitamin D3 deficiency

Vitamin D3 deficiency causes a variety of symptoms, including, but not limited to: 

• Bone pain
• Bone loss 
• Hair loss 
• Muscle cramps, soreness, and weakness 
• Unusual fatigue even after having a rest 
• Changes in mood or mood disorders 
• Impaired immune response 
• Cognitive decline and lack of focus 
• Impaired wound healing 

Symptoms of vitamin B12 deficiency

Vitamin B12 deficiency may lead to a range of symptoms, such as: 

• Sleep issues 
• Anemia or blood lacking enough red blood cells 
• Memory loss, decreased cognitive function, and confusion 
• Seizures 
• Dementia 
• Depression 
• Nerve damage with a tingling and numbness sensation in the legs and hands 
• Shortness of breath and uneven heart rate 
• Lightheadedness, dizziness, weakness, and fatigue 
• Vision loss 
• Pale skin 
• Smooth tongue 

Why you might need vitamin D3 and B12 supplements 

Vitamin D3 and B12 supplements may make sense for most of us, especially in older ages. Even though we remain on a perfect diet, we are still likely to develop insufficiencies of these two vital nutrients. Why? Let’s figure it out.  

As we age, our ability to make vitamin D from sunlight declines. Though the revised minimum recommended intake of vitamin D for elderly people is now considered to be 25 mcg (1000 IU) a day, the optimal level of it is still unknown. Therefore, most clinicians recommend 2000 IU to 4000 IU per day to get the best of it. Attaining this requirement with diet alone is literally not possible since most dietary sources do not contain vitamin D in a staple amount. Besides, exposure to the sun may increase the risk of certain types of cancer. 

Vitamin D3 is more efficient and better absorbed in the body compared to other forms of vitamin D. This is the main reason most clinicians recommend vitamin D3 supplements to combat its deficiency. 

Vitamin B12, on the other hand, is found in only animal foods and we typically cannot get it from plant-based foods. Besides, our ability to absorb its natural form declines with aging mainly due to less stomach acid production.

Moreover, certain medications such as diabetes medications and antacids may also hinder the absorption capacity of vitamin B12. These issues are usually known as malabsorption. Certain gastrointestinal problems such as celiac disease and gastric issues may also affect our ability to access this vital vitamin too. 

According to Federal Dietary Guidelines, a daily intake of vitamin B12 recommended for adults is 2.4 mcg. Most people find vitamin B12 supplements as the easiest option to maintain a healthy level.   

But before you pick up any vitamin D3 and B12 supplements, it makes sense to have a consultation with a certified natural medicine healthcare provider to determine your safety and best method of use.

Here you can see Vorst’s pure and natural Vitamin D3 25 mcg (1000 IU) Capsules 

Here you can see Vorst’s pure and natural Vitamin B12 with Melatonin Capsules 

Important resources: 

1. https://www.ajhospital.in/news/what-is-the-importance-of-vitamin-d3-and-b12-in-your-diet
2. https://www.webmd.com/diet/vitamin-b12-deficiency-symptoms-causes
3. https://www.hsph.harvard.edu/nutritionsource/vitamins/vitamin-b/
4. https://blog.mission-health.org/2020/02/28/supplements-seniors-vitamins-d-and-b12-essential/
5. https://www.aarp.org/health/healthy-living/info-2021/vitamin-b12-d3.html
6. https://timesofindia.indiatimes.com/life-style/health-fitness/health-news/vitamin-d3-and-b12-deficiency-is-a-silent-epidemic-linked-to-your-immune-system-brain-and-hormonal-health/photostory/92386871.cms?picid=92386894