Popping back nutritional supplements is a great way to complement a healthy diet and support your body where it needs it most. A multivitamin is the easiest route for many people to get everything they need in a single punch.

But here's the catch with vitamins and minerals—they're not all designed to be taken simultaneously. Some inhibit the absorption of others, some require fats for absorption, and some should be taken on an empty stomach, while others require food.

Planning out your supplement schedule can be hard work, but when you find a multi that's complexed with compounds to boost absorption, you can put all your absorption worries behind you.

We'll cover the details on the only multivitamin you need, but right now, we're diving into two essential water-soluble vitamins that must be in your stack—vitamin C and vitamin B12.

They're required for everything from immune health and antioxidant defenses to energy production and cognitive function. This article dives into what you need to know about supplementing them together.

The Basics Of Vitamin C And B12

Both vitamin C and vitamin B12 belong to the group of water-soluble nutrients. While some mammals can produce vitamin C, humans aren't one, which means it must come through diet or supplementation. And because it's not stored in the body, it must be consumed daily to maintain levels.

Although most of what we hear about vitamin C has to do with boosting immune function and cutting the common cold short, that only scratches the surface of what it offers.

Aside from immune function, one of the most powerful functions of vitamin C is its antioxidant properties. It works with vitamin E to regenerate vitamin E and extend its free-radical fighting properties 1. But there's more to it.

Vitamin C is involved in:

  • Collagen synthesis
  • Wound healing
  • Immune defenses
  • Blood vessel health
  • Improving cardiovascular disease risk factors
  • Reducing uric acid levels
  • Absorption of non-heme iron
  • Cognitive function

Vitamin B12, on the other hand, is another water-soluble nutrient that's generally found combined with the other B vitamin in a complex.

Sometimes referred to as cobalamin, vitamin B12 plays an essential role in energy production, along with red blood cell formation (hematopoiesis), DNA synthesis, brain development, nervous system function, fatty acid synthesis, and myelin formation (nervous system) 2.

Vitamin B12 is involved in:

  1. Red blood cell production
  2. Energy production
  3. Bone health
  4. Mood
  5. Cardiovascular function
  6. Hair, skin, and nail health

But while you may be consuming enough B12 through diet, how much gets absorbed depends on your levels of a protein called intrinsic factor (IF).

Intrinsic factor is produced by parietal cells of the stomach and binds B12 to allow absorption in the intestines 3. It forms an IF-B12 complex that will enable B12 to enter systemic circulation.

However, it's important to note that while vitamin C and B12 are both essential for optimal biological function, some research suggests that taking vitamin C alongside B12 can impair absorption of B12, so it's recommended to separate your doses.

Deficiency Signs And Symptoms

Although vitamin C and B12 are widely available in many food sources, deficiencies aren't uncommon. Vitamin C deficiency typically manifests after about 8-12 weeks of insufficient intake and presents as 4:

  • Irritability
  • Anorexia
  • Poor wound healing
  • Swollen gums with loss of teeth
  • Bleeding of the skin and mucous membrane (mucocutaneous petechiae)
  • Skin discoloration (ecchymosis)
  • Increased thickness of outer skin (hyperkeratosis)
  • Dry eyes
  • Alopecia

Some of the most common symptoms of vitamin B12 deficiency include:

  • Numbness or tingling in hands or feet
  • Muscle weakness
  • Difficulty walking
  • Nausea
  • Low appetite
  • Weight loss
  • Irritability
  • Fatigue

4 Benefits Of Taking Vitamin C And B12

1. Healthier Skin

Both vitamin C and vitamin B12 are involved in the health of tissues. As a critical component of the body's immune defenses, especially in the skin, vitamin C acts as an antioxidant to fight free-radical damage and strengthen the skin's barriers 5.

Vitamin C is also involved in collagen production because it's a cofactor for procollagen proline and lysine hydroxylase, making it a vital compound to maintain the skin and other tissues 6.

And when you combine that with vitamin B12, you're getting an even bigger boost. Because vitamin B12 is involved in cell production, it helps to promote healthy skin, hair, and nails.

Low levels of B12 can result in dermatological issues like hyperpigmentation, nail discoloration, hair changes, vitiligo, and inflamed and cracked corners of the mouth 6, 7. But it can improve symptoms when you bump your levels back to the normal range 8.

2. Protects Memory And Thinking

Need a brain boost? A little vitamin C and B12 could help! Studies suggest that memory impairment can result from oxidative stress and inflammation in the central nervous system 9. Vitamin C is an important antioxidant, and low levels have been linked to impaired memory and concentration.

An older study looked at the link between nutritional status and cognitive function in 260 men and women over 60 10.

Subjects with low vitamin C and B12 scored worse on tests for abstract thinking ability and memory, suggesting that subclinical malnutrition may influence cognitive function.

And several studies show that higher levels of vitamin C and B12 can help protect against cognitive decline and memory impairment 11-13.

3. Support Heart Health

Both vitamin C and vitamin B12 are essential nutrients for protecting the heart and reducing disease risk.

Vitamin C reduces some risk factors linked to heart disease, including high blood pressure, high triglycerides, and low HDL.

A meta-analysis of nine studies found that people taking at least 700mg of vitamin C daily reduced their risk of heart disease by 25% 14. Another study found that 500mg of vitamin C daily reduced LDL cholesterol and blood triglycerides 15.

Vitamin B12, on the other hand, may reduce the risk of heart disease via its role in lowering homocysteine levels. Homocysteine is an amino acid that can become elevated in the bloodstream when B12 levels are low.

B12 is required as a cofactor to convert homocysteine to its less toxic amino acid, methionine. High levels of homocysteine increase CVD risk because of its effects on vascular endothelium and smooth muscle cells, which subsequently alter arterial structure and function 16.

However, sufficient intake of B12 (along with B6 and folate) supports that conversion process and helps keep homocysteine levels low or within a normal range 17, 18.

4. Red Blood Cell Formation

Although vitamin C doesn't have a direct role in hematopoiesis, it indirectly contributes by helping the body absorb iron from plant-source (i.e., non-heme iron). Iron is critical for red blood cell formation as it forms the heme component of hemoglobin, the oxygen-carrying protein in blood cells.

But for people following a plant-based diet, adequate intake can be hard to achieve, as non-heme iron has low bioavailability. However, vitamin C taken alongside iron can boost absorption by up to 67% 19. It can help reduce the risk of anemia in people prone to iron deficiency.

Vitamin B12 also plays a crucial role in red blood cell formation. Low levels of B12 are associated with reductions in RBC formation and improper development—they become larger and more oval with low levels of B12 and can cause megaloblastic anemia 20.

Because blood cells are irregularly shaped, they cannot move from bone marrow to the bloodstream at an appropriate rate, which results in anemia and symptoms like fatigue and weakness due to low oxygen saturation in tissues.

Where To Find Them

If you're looking to maintain optimal health and performance, getting enough vitamin C and B12 is non-negotiable. While they're widely available in food sources, why not stack them in a good multi? It's a simple and convenient way to consume them.

Performance Lab NutriGenesis Multi supplies 100% DV of 17+ essential vitamins and minerals—including vitamin C and B12.

And because NutriGenesis nutrients are nature-identical and complexed with cofactors for maximum absorption, you know your body is using what you're taking.

It's the smartest and most effective way to ensure your body gets the nutrients it needs to perform at the highest level.


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