Immune Health and Vitamin C

As more and more people are learning about nutrition and the impact it has on their overall wellbeing, immune health is becoming one of the fastest growing areas of interest among those hoping to remain healthy. When considering the nutrients we should ensure we get enough of, it's hard to look past Vitamin C. It has been classified as an essential vitamin for good reason, and the studies showing the positive effects it has on our bodies are quite impressive. This article will summarize what certain studies are finding out about Vitamin C, the effects it has on the immune system, and why it is one of the most popular dietary supplements.

Vitamins are classified as being 'essential' when they are of a type that the body does not produce naturally yet are required for normal function. Vitamin C fits this category because of the many roles it has in maintaining basic biological functions. It is soluble in water and is found in many fresh fruits and vegetables. Citrus fruits such as oranges and lemons are an excellent source of Vitamin C, as are certain vegetables and berries. Eating balanced meals containing Vitamin C rich ingredients every day is common advice that many people find is suitable for reaching their recommended daily intake of this nutrient. With the RDI set at 75mg for women, and 90 mg for men [1], simply having daily servings of fresh fruits and vegetables is sufficient for most people. Alternatively, many people choose to get their Vitamin C by taking a supplement that contains it.

Quick Facts About Vitamin C

Vitamin C is Water Soluble

Commonly Available in Fruits and Veggies

Recommended Daily Intake for Women: 75mg

Recommended Daily Intake for Men: 90mg

Cannot be Produced by the Body, Therefore Considered Essential

Vitamin C – A Powerful Antioxidant

Vitamin C is an antioxidant. An antioxidant is a sort of molecule that is shown to enhance the immune system by protecting cells from free radicals [2], which are harmful molecules linked to many chronic conditions. Free radicals can accumulate and enable a situation known as oxidative stress [3]. Studies show that Vitamin C aids the immune system to fight inflammation and consuming more of this nutrient can raise the levels of antioxidants found in the blood by as much as 30% [4][5].

Antioxidants like Vitamin C, which help fight inflammation, are valuable to those that seek to minimize the risk of chronic conditions such as heart disease. Another area that Vitamin C shows promise is helping reduce blood pressure [6]. Almost a third of adult Americans have high blood pressure, which is often seen as a precursor to heart disease [7]. Heart disease is the number one cause of death in many countries worldwide.

Vitamin C and Heart Disease

Studies have shown that Vitamin C may help lower blood pressure. In fact, data from 29 human studies demonstrate that taking a Vitamin C supplement reduced systolic blood pressure by up to 3.8 mmHg, and diastolic pressure by up to 1.5 mmHg. These results are an average found among healthy adults. This analysis has also shown adults diagnosed with high blood pressure on average experienced reduced systolic pressure by 4.9 mmHg, and diastolic blood pressure by 1.7 mmHg [6].

An analysis was conducted to investigate risk factors of heart disease. The analysis consisted of 9 studies, and 293,172 individuals took part in these studies. The findings were, after a 10-year span, participants who had ingested at least 700 mg of Vitamin C on a daily basis had a 25% lower risk of heart disease than those who did not take a Vitamin C supplement [8].

Researchers are uncertain if this data is coincidental and the individuals who exhibited the tendency to consume more Vitamin C had better health habits than the participants who did not take a Vitamin C supplement [9]. It is also important to keep in mind that although the studies report this data, it remains unknown how long these effects last. Studies such as these, while exciting to learn about, should not suggest Vitamin C as an alternative remedy for high blood pressure. Patients diagnosed with high blood pressure should not seek Vitamin C as an alternative to their prescribed medications. Always follow your doctor's advice and discuss any supplements you plan on taking with them.

One of the glaring risk factors associated with both high blood pressure and heart disease is cholesterol. Cholesterol levels are described by the levels of good (HDL), bad (LDL), and triglyceride count. After analyzing the results of 13 studies, researchers found that the participants who took at least 500mg of Vitamin C daily had significant LDL reduction, by about 7.9 mg/dL, and triglyceride counts decreased by approximately 20.1 mg/dL [10].

Vitamin C May Reduce Uric Acid Levels

Another study suggests Vitamin C can be helpful in reducing the amount of uric acid levels in the blood [11]. Uric acid is produced as a waste product by the body. Sometimes when the levels are high enough, uric acid will collect around joints and crystallize, causing severe pain and inflammation. The simple term used to describe this occurrence is gout [12]. Gout is a type of arthritis, and it affects proximately 4% of the adult American population [13]. One of the studies, which followed 46,994 participants over the course of 20 years, found that those who took a Vitamin C supplement had a 44% lower risk of developing gout [14]. An analysis of 13 separate studies revealed that, over the course of 30 days, those who took a Vitamin C supplement had significantly less uric acid in their blood than those in the study taking a placebo [15]. Though there appears to be a strong connection to lowering uric acid levels, more studies are needed before Vitamin C can be considered to be the cause of these results.

Summary of Findings

Vitamin C meets all the criteria to be considered an essential nutrient. There is quite a bit of research that suggests it may be beneficial as a powerful antioxidant. Research studies have explored the effects of higher doses of Vitamin C in many individuals in a wide variety of contexts. As with any supplement, strictly follow any advice given to you by your doctor first. Consult your doctor before deciding to take any supplement products, especially if you have a health condition or are on any medications.

1) https://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/

2) https://journals.humankinetics.com/doi/abs/10.1123/ijsn.7.1.1

3) https://www.ncbi.nlm.nih.gov/pubmed/23675073

4) https://www.ncbi.nlm.nih.gov/pubmed/12805247

5) https://www.hindawi.com/journals/omcl/2015/295497/

6) http://www.ncbi.nlm.nih.gov/pubmed/22492364

7) http://www.who.int/mediacentre/factsheets/fs317/en/

8) https://www.ncbi.nlm.nih.gov/pubmed/15585762

9) https://www.ncbi.nlm.nih.gov/pubmed/18277182

10) https://www.ncbi.nlm.nih.gov/pubmed/19674720

11) https://www.ncbi.nlm.nih.gov/pubmed/21800283

12) https://www.ncbi.nlm.nih.gov/pubmed/21569453

13) https://www.ncbi.nlm.nih.gov/pubmed/18464304

14) https://www.ncbi.nlm.nih.gov/pubmed/19273781

15) https://www.ncbi.nlm.nih.gov/pubmed/21671418