Vitamin C May Affect Blood Pressure

Researchers have found a possible link between high levels of vitamin C (ascorbic acid) and lower blood pressure in women.

Vitamin C is a water-soluble vitamin that is commonly found in fruits and vegetables, such as broccoli, grapefruits, lemons, limes, oranges, peppers and tomatoes. It has antioxidant effects and is needed for the body to form cartilage, muscle, blood vessels and collagen in bones. It also helps the body absorb iron.

The authors studied 242 women, between the ages of 18 and 21, who participated in the National Heart, Lung and Blood Institute Growth and Health Study. The participants were 8-11 years old at the start of the 10-year-long study. Their blood pressure and vitamin C levels were measured throughout the trial.

After adjusting for race, body mass, education and dietary intake of fat and sodium, the authors found that higher vitamin C levels were associated with lower systolic and diastolic blood pressure levels. People with the highest vitamin C levels (about 1.83 milligrams of ascorbic acid per deciliter of blood) had 4.66mmHg lower systolic blood pressure and 6.04 lower diastolic blood pressure compared to those with the lowest vitamin C levels.

However, diets high in vitamin C may also contain other nutrients that affect blood pressure, such as fiber. Therefore, additional research is needed to determine if vitamin C has blood pressure-lowering effects.

For more information about vitamin C, please visit Natural Standard's Foods, Herbs & Supplements database.

Comments

[BG]

The sample of this study was rather young. Participants were 8-11 years old at the start, and it ran for 10 years. Are the results of this study generalizable to the greater population? Also, what about the parents? It would be interesting to see if the entire family is eating healthier, and who or what (Parents? Friends?) is reinforcing the kind of eating habits that lead to these positive outcomes.

The articles mentions, “Diets high in vitamin C may also contain other nutrients that affect blood pressure, such as fiber.” This is important because the entire diet needs to be assessed, as well as physical activity level (the data were only adjusted for race, body mass, education and dietary intake of fat and sodium), which presumably affects blood pressure.

Also, it is controversial in some circles to stratify/adjust data by race, and it is slated to be better to adjust by socio-economic levels (in this case, by family income). If it were fiscally feasible, it would be interesting to see what these outcomes look like in 40 or 50 years.

[Stephen Lawson]

A number of small clinical trials have already been published demonstrating the blood pressure-lowering effects of vitamin C supplements in hypertensive subjects. Check PubMed for references.

[Luce]

How much vitamin C did the study participants take on a daily basis? Also, were they healthy individuals or individuals at risk of developing hypertension? What if I increased my daily intake of citrus fruits and other foods containing vitamin C? Will this have an impact on my blood pressure?

[Ruby]

This study has several limitations: it only studied vitamin C in women, so these results cannot be applied to men, pregnant women who may have gestational hypertension, or the elderly population (which usually has blood pressure issues). The trial was also focused on a very narrow age group, and this age group does not usually display blood pressure issues. This study would have been more meaningful if men were also included and if it was done in the elderly population, which would benefit the most from this. I have not looked at the study specifically, but based on the info provided above, the dose of vitamin C used in the study for blood pressure lowering-effects is not stated. I don't recommend drawing conclusions from this study alone; further research must be done on this topic.

[RZD]

Was there a particular reason that the study was only conducted in women?

[DL]

Wouldn’t it be nice if the cure for high blood pressure was more oranges (or kiwis!)?. I wager you’d see a lot more pharmaceuticals starting plantations to make up for their lost profits. Unfortunately, this study is several steps removed from making any sort of solid statements about vitamin C saving lives (correlated with lowering blood pressure in healthy young women->lowers blood pressure in healthy young women->lowers blood pressure in adults->leads to lower incidence of heart disease), but I imagine finding the answers will be quicker and cheaper than with whatever the next heart medication coming down the pharma pipeline.

[g.h.]

Great that they found something else that vitamin C is good for, but this study seems crazy. A population of 8-11 year olds is not going to have high blood pressure. Would you see this much of a decrease with an older population with hypertension where this information would be more relevant?

[Luce]

It would have been better if the researchers mentioned why they studied this particular age group since the participants do not even fall in the bracket of populations that suffer from hypertension. However, despite the flaws of this study, we could say that maintaining adequate vitamin C intake in our children could eventually reduce their risk of developing hypertension in the future, especially in those with first-degree relatives who have hypertension or heart disease.

[Maria C.]

Well it's good to know that taking vitamin C at a young age will be beneficial for later health. I agree with many of you, and I wonder why they chose this certain population of young women to conduct the study in. Maybe, they were investigating how important healthy eating and vitamin intake are during growth and development. Researchers are also beginning to find that health problems in adulthood can stem from childhood eating practices.

[VLN]

If the results of this study are truly significant, this is great news. As mentioned in the blog, vit C is used for so many things in the body, and if we are able to have it also lower blood pressure, it can't hurt. Is the amount of vit C found in multivitamins sufficient to see these effects?

[uwan]

Very useful information. This is very good as a natural treatment for hypertension, but not good for people with acid reflux disease.

[Luk]

VLN,

Remember that the amount of vitamin C in multivitamins is said not be enough to prevent one from having a common cold, so it's probably not the same for lowering blood pressure.

[Lesley]

What if I maxed out my daily intake of vitamin C? Will this have an impact on my blood pressure, like lowering it or maintaining it in the normal range?

[Sam]

How much vitamin C did the study participants take on a daily basis? Stating that they had diets high in vitamin C is not enough. The amount taken, frequency and duration needs to be stated so others can implement on themselves or in their patients.

[LC]

I wonder if the researchers will continue to monitor the participants of the study? As others mentioned, this age group is typically healthy, and perhaps if they still have low blood pressure at say age 50, then the results would be more valuable. To me, it indicates what is already commonly known -- that a healthy diet (rich with vitamin C too!) when you're younger will increase the chances of a healthy adulthood.

[Isabella]

The trial focused on a very narrow age group that doesn't normally exhibit blood pressure problems.

[Lucy Lu]

I don't think that this study is valid. The age range is too young and women are less likely to develop hypertension than men. You can almost predict the results of the study beforehand. If it were to really work, I think you would need too much and it wouldn't be realistic.

[Sarah]

A pilot study by Adam Mousa and Shaker Mousa wrote in the Journal of Nutrition Research (Elsevier) that a combination of garlic supplements and vitamin C reduced blood pressure back to normal levels in people with mildly elevated levels.

[Tracey]

Green tea has been linked to heart and cardiovascular health as it improves both blood flow and the ability of your arteries to relax. One 2007 study discovered that complementing green tea with either citrus juices or vitamin C increases the amount of catechins available for your body to absorb.

[Manda]

I'll merely repeat other comments by asking why they chose such a young study population. Maybe they wanted to be sure to have positive results? Even if this study was repeated but started the 10 year follow up in 50-year-olds, the data would be a bit more useful.

[Shawn]

I think this study is a step in the right direction, especially with such a prevalent vitamin. The biggest qualm I have with this study is the fact the patients BPs could just be lower due to a healthy diet of fruits and veggies as opposed to greasy cheeseburgers. Also, to really validate the results and make this an impact study, the researchers need to continue to follow the patients for 10-20 years more.

[TPS]

I absolutely agree with the comments regarding the age of the participants that were studied. Personally, I looked at stress levels being a possible factor in high or low blood pressure. We start developing dieting and exercise habits at a young age, which may set the tone on how we take care of our health. I think in general we can agree that high levels of stress will ultimately lead to higher blood pressure. Can we correlate with higher vitamin C levels with being more health conscious? Personally, I think having health awareness (in this case proper diet and exercise) may lead to less stress and an overall wellbeing. That being said, perhaps that may actually lead to a lower blood pressure than someone who is highly stressed without proper dieting and exercise.

[AJ]

Preventing hypertension during young adulthood to help minimize chances for hypertension later on in life is a great idea for a study. However, as mentioned earlier, this study looked at patients who were unlikely to have hypertension problems. This study would serve a better purpose if it examined the role of vitamin C in an older population who had pre-hypertension or hypertension already.

[Arihant Kothari]

As suggested by someone here, the sample taken was relatively young and, in fact, there are many benefits of taking high-dose vitamin C in various forms.

http://www.goji-juice.co.uk

[AJ]

This study did not mention if there is a difference between Vitamin C supplements vs. food sources. Would there be a difference?

[MHD]

I always hold a level of speculation when reading studies focused on one particular dietary nutrient. The reason why I do this is because I wonder if it focuses on how much the subjects are eating of one particular nutrient, in this case vitamin C, or if it is an assessment of their diets as a whole. It can be assumed that if a person consumes high levels of vitamin C, they have a more well-balanced diet. And is it a combination of factors that lead to its efficacy as an antihypertensive nutrient? Whatever the case, vitamin C has been proved to be good for you, your skin and the fight against cancer. So eat up!

[cptan]

Great and nice article and information for everyone. I agree with your information, and thanks for sharing. GOOD blog, and keep posting.

[Larry]

There have been many great studies involving vitamin c. It is no surprise that utilizing it to improve body function in regard to blood pressure has shown a positive correlation. Another interesting study that has come out over the last year or so is that upper cervical specific chiropractic has proven to lower blood pressure as well/if not better than two blood pressure medicines combined.