The effects of vitamin D deficiency and insufficiency go well beyond those of rickets and bone health and can affect anyone at any age. GrassrootsHealth has been sharing practical and reliable information about vitamin D for over 15 years while running the world’s largest public health intervention study on vitamin D.  Over those years, we have received many stories from individuals of all ages describing how vitamin D has changed their health and lives. Below we share several of those stories.

Help Increase Awareness by Sharing Your Story Too

We believe many of you have stories to share about how vitamin D impacted your health, and we ask that you share them with us so that we can forward them on. Your story could motivate others to consider learning more about vitamin D for their own health and lead them to take the right steps towards making a world of difference in their health and their life. It is a simple solution – you can help build the awareness!

Do you have a story you would like to share?

Share it Here

Email [email protected] if you are interested in a detailed participant interview!

Featured Participant Stories

The following stories have been previously featured on the GrassrootsHealth website.  To view these and more, visit the Testimonials section of our blog.

How Vitamin D Changed the Life of a Doctor with MS – Her Journey and an Interview

The following is a narrative by Satya L. Nahu, MD.  The Coimbra Protocol has helped thousands around the world overcome their autoimmune diseases using extremely high doses of vitamin D. Do not treat yourself without the guidance of a skilled practitioner…  Read More


Disturbing Trends among Teenagers – How Nutrients CAN Help

“Mom… I feel like I’m dying.” The latest statistics show that almost 60% of teenage female students experienced persistent feelings of sadness or hopelessness and nearly 25% made a suicide plan. One mom’s story could help many others.  Read More


Participant Story: Why I Keep My Vitamin D Above 100 ng/ml

The GrassrootsHealth panel of scientists recommends a vitamin D level between 40-60 ng/ml; what happens when higher levels are maintained? Bob is a long-time participant in the GrassrootsHealth D*action project who shares his story here.  Read More


Vitamin D Can Turn Your Health Around

Vitamin D has helped me to walk, to sleep, to get off medication; After many years of research and personal use of vitamin D, I strongly believe in the preventive and curative powers of vitamin D for cancer and other health problems.  Read More

Additional Participant Stories and Testimonials from Over the Years

Prostate Cancer Reverted

To say my wife and I are blessed is an understatement. We live in Toronto but are hardly ever there since retiring in 2002.

We love biking, golfing, and skiing, which we do in beautiful Muskoka, Los Cabos, St. Anton, Austria, and Whistler, BC. We call it the “Great Migration Circle.” Did I mentioned we are spoiled?

Anyway, a little rain fell in 2007 when I was diagnosed with prostate cancer. I won’t bore you with all the alternative things I have done to keep my prostate intact.  One of the more important things I did was get involved with GrassrootsHealth in their “guinea pig” program on vitamin D3 and cancer.

I have been taking 8,000 IU’s of vitamin D3 for at least a decade now with no ill effects.  On the contrary that hormone called D3 has been very helpful for my overall health.

Do I still have my prostate that was diagnosed as having cancer in ‘07 intact because of supplements like D3? Possibly… all I know is I still have it.


Biking in Tahiti in May followed by a 2nd bike trip to the British Isles.
Some 700 Km in the month. Not bad for a 77yr old.


P.C. (2024)

Thanks, from a Long-Time Participant

For fifteen years I’ve been a participant with GrassrootsHealth. Initially I hoped (simply) for a test but came to a place of opening up to the importance of joining this study. I am very glad I pursued this. It’s a community that I continue to develop trust in its offerings and its total commitment to broaden its reach to many others, to counter the shockingly false/misleading/unhelpful information that pervades our public space, and inspire us to see the huge implications to an individual and a community of low vitamin D levels. My Vitamin D level was less than 30 ng/ml and I had a fairly steady incidence of colds which now seem to be a thing of the past.

I take about 3500 to 5000 I.U. of Vitamin D3 nearly every day. I didn’t have any significant health problems but felt that I wanted to learn as much as I could about Vitamin D from articles I had read – I thankfully found GrassrootsHealth and have stayed.

I was extremely relieved to not get Covid and have not had a flu or cold during the time of bringing my Vitamin D levels to a steady 40-60 ng/ml (or sometimes higher). I spend more time (carefully and informatively) in natural sunlight primarily because GrassrootsHealth has been very helpful and knowledgeable in teaching me about other benefits of sunlight (particularly UVB). Friends ask me how I’m so healthy and I talk about Vit. D primarily and responsible sunlight, as well as GrassrootsHealth, an organization I have the highest respect for.

In addition to vitamin D I also now test for:
Omega 3 index; omega Ratio; AA:EPA Ratio; hbA1c; hs-CRP; Mg plus Elements; TSH

I take supplements based on my results and have been pleased to see my numbers move to better readings. I intend to keep up with this and keep reading GrassrootsHealth nutrition studies/reports/videos and suggestions.

A few times I have reached out to GrassrootsHealth and their responsiveness and helpfulness has been consistently remarkable.

In addition to Vitamin D, I take Vitamin C, Magnesium, a combo of trace minerals; Omega 3 and Vitamins E and A.

I live in Austin Texas and was a psychotherapist for many decades. I’m mostly retired now and spending more time out-of-doors, swimming, walking, and some exercise at the gym. I have plenty of energy.

Join in – it is the best health practice I can unequivocally and highly recommend.

Thank you all for your dedication to science – and to us, your participants.

R. A. (2024)

How GrassrootsHealth Influenced Our Health

I am writing to communicate my appreciation for the services that GrassrootsHealth provides. The testing and results have been very useful, and I appreciate the information provided through your daily communication.

My wife and I have been taking Vitamin D and fish oil supplements for almost two decades. I have been retired for 8 years, my wife for 15. I discovered GrassrootsHealth in 2016 and since then testing results have allowed me to actually see the impact of our supplementation and adjust accordingly. Our Vitamin D levels are a bit difficult to manage because of our lifestyle. We live in Alaska during the summer and in Arizona in the winter. Sun exposure is the variable. We receive some benefit to exposure at high latitude from May to mid-July, very little from mid-July to November and Arizona exposure November through March. In many of our exposure months we are covered either due to ambient temperatures or flying pests. Since we are Alaska based, our meat intake is, by majority, salmon.

I do have to mention that the testing, however beneficial, it a bit expensive for someone living on a fixed income. I do appreciate that GrassrootsHealth was responsive to my request recently to modify our invoice to provide detail enough that our insurance and HSA will potentially accept the testing as reimbursable. For us, I believe we have a long enough track record to not require testing every six months. I now do it whenever there is a change in our supplementation and I want to understand the impacts.

Neither of us has had the flu since we began supplementing. My wife has had a couple of flu shots, I have never had a flu shot. I have not had a cold since 2012. My wife has had two instances where she got the sniffles after our grandson visited with a full-blown cold. I did not pick anything up after those visits.

This last winter, as COVID fatigue and reduced incidence rates drove more travel, we were visited three times by couples who stayed with us for a week or more each. Interesting to us is all three notified us two days after leaving that they tested positive for COVID. We tried to be smart about exposure and distancing but we did spend many hours in a car with them travelling and showing them the sights. Neither one of us contracted the disease. It’s not that we were asymptomatic and gave the visitors the disease because each of them was able to trace their exposure to before they arrived at our house.

I understand there are several factors involved with transmission and susceptibility to contagious diseases. It could be we were lucky and missed the COVID bullet. We believe that our supplementation, managing food and exercise lifestyle all contributed to our not getting COVID although we were definitely exposed more than once. I firmly believe that GrasstootsHealth played a significant part in our continued health and I am grateful.

K.H. (2022)

Noticeable Differences

Up until Nov. 26,2020, my wife and I never took any supplements, ever. What a difference a day (or 60) make!

After unknowingly coming into contact for five minutes with a neighbour who was Covid positive, he then told us he tested positive for it. Two days of waiting for my own Covid test results were filled with apprehension and doubt of my own survival. Fortunately, the test was negative. Thanks to my neighbour, I began a quest to see if there was anything I could do to help ourselves.

Medical knowledge is not my forte, but computers are. I view the Internet as a grand learning tool, and so I delved into the world of Covid medical knowledge and kept coming across an unfamiliar name: Dr. M. Holick. It didn’t take me long to realize this man was onto something with Vitamin D3. My extent on the subject related to my own dog. A trainer in a video said to never give D3 to a dog because D3 could kill it.  The clarion call message from Dr. Holick to me was that D3, among other things, acted as an immune system regulator. Having been overexposed to petrochemical products in the late eighties and early nineties, my immune system was out of kilter for years, along with numerous bouts of pneumonia.

After reading many research papers and trials on PubMed, I was convinced D3 was our best bet to try and protect us from the serious ravages of Covid. The question then became: How much should we take to become D3 sufficient?

Well, the answer came from an unlikely source: in a paper written by Simon Goddek. In his published paper on D3 and K2, he hypothesized that someone could possibly raise their D3 levels from 20ng/mL to 40ng/mL by following a table of D3 and K2 dosages based on weight.

We decided to follow that information, along with the suggestion of taking Magnesium. We did not get a baseline D3 test first, but we did get tested eight days after the top up (to give the liver a chance to catch up.)

My 25(OH)D is 138nmol/L (55.2ng/mL) and my wife’s is 155nmol/L (62ng/mL). We feel much better that we may now, one month after the D3 test results, have a better chance of surviving a bout with Covid. We do not plan on staying at those numbers. My wife is aiming for 80ng/mL and I am aiming for 100ng/mL. She is currently taking 10,000IU of D3 and I am taking 15,000IU per day (reducing to 10,000IU in mid February). We also take: 360mcg K2, 300mg Magnesium citrate and 900mg EPA/DHA daily along with 50mg of Zinc citrate every other day.

Considering our northern climates, we depend on D3 by supplements right now. Come June, my wife will reduce her D3 supplements a bit and get out in the midday sun each day. For me, I will remain on 10,000IU daily unless I get some decent sunshine without burning (light eyes, light skin).

We signed up for the five year study and will submit blood for D3 and Omega-3 testing twice a year.

Two months from the start of the D3 journey and we both feel more energetic and I feel much less foggy in the morning. And my skin seems to be getting a bit less wrinkly (or so I think it is). The psoriasis on my face is about gone too – baking soda used to take care of it.  In the long-run, we plan on keeping up our D3 levels to get as much gene expression as possible.

G.H. (2021)

Itchiness and Gingivitis Improved

When I look at the list of symptoms of vitamin D deficiency, absent are the two ailments which I was experiencing and which clear-up or significantly after I began supplementing with sufficient vit D to get my blood level to 40 ng/ml.

1. Dry flakey itchy shins: This totally cleared up and stopped being itchy.
2. Gums which bled profusely when brushing my teeth. The bleeding became greatly reduced and focused to an area where I had an abscess. After the abscess was treated and my other dental work was completed the bleeding has totally stopped. In the past after dental work the bleeding did not stop. Only this time did it stop.

When I looked up dry, itchy, flakey skin and vit D, it popped up as an indicator of low vit D. Likewise when I looked up vit D and gingivitis many studies came up indicating that gingivitis and periodontal disease could include low vit D as a cause. I would like to see those conditions added to the list of symptoms of low vit D.

J.O. (2021)

Improving Health Conditions and Getting Off Medications

The first 30 years of my life were filled with illness, doctor’s visits, and prescription drugs. Then, a co-worker shared with me what he had learned about vitamins and that inspired me to make changes. I went to the library (before the worldwide web came along) and read everything that I could about vitamins, minerals, and nutrition. That led me to try various vitamins, supplements, and make diet and lifestyle changes, all of which I had read about for helping my health conditions. Before long, I was much healthier than I had ever been and was able to stop all the prescription drugs, even though my doctors told me that I was wasting my money on vitamins and would only have “expensive urine.” Based on my now 30+ years of studying natural health, last year I became a Certified Health Coach in order to help as many people as possible make changes so THEY can reach the Optimal Wellness that I have!

GrassrootsHealth has given me more information and facts about vitamin D and omega-3 fish oils than I could ever have found on my own! I’ve been sharing what I’ve learned with my friends and family for years and some have told me that they seem to have become more knowledgeable than their doctors about vitamin D — their doctors still tell them that a D3 blood level of 30 ng/ml is “fine” or they tell them to stop taking D3 if the level goes over 50, so I’ve recommended that they share some GrassrootsHealth data with their doctors.

H.N. (2021)

Responsibility to My Health and the Health of Family

Growing up I was always pleasingly plump. I come from a farming background both as a child and my married life. The day I turned 20 I got married, still 5-6 pounds heavier than I wanted to be. That winter I lived on love, coffee with cream and sugar, and yes, I did lose those 5 pounds. By spring I was hospitalized with malnutrition. Being told that was like getting hit by a freight train. It was time for immediate action. Really, suffering from malnutrition in the 1970’s in Canada!!! I studied nutrition, lifestyles and made myself a promise. “Never would this ever happen again to me and it was my job as a wife and eventually a mother to keep my family healthy”.

My plan was to eat healthy, wholesome foods and keep fit. I simply cut sugar and would go outdoors everyday either for work or play. We were a healthy family. At 60 years old I got hypothyroidism but my weight did not change. Around 2010 I heard about GrassrootsHealth and was curious if my efforts were yielding positive results. So I joined and was thrilled that my efforts had paid off. Now after being married 51 years, having had 2 daughters I am still healthy and at my ideal weight.

Simple changes yielded huge positive results for me. GrassrootsHealth re-enforced what I was doing was keeping me healthy. I did get my elements checked and was in the zones I should be.

R.F. (2021)

Feeling Young and Healthy, Boosting the Immune System

These past 2 years of the pandemic, knowing that certain natural remedies like vitamins D and C and zinc and other healthful ways of building your immunity up for me and my wife has helped us to stay healthy. Even when we have gotten the flu, colds, covid-19 and have asthma, we only felt tired, no fever and no worsening of asthma. I have been using an inhaler for many years and since taking 5000 IU vitamin D I haven’t had problems with asthma for over 2 years now. I am 74 years young, so to me natural way is the only way for me and my wife of 66 years young. GrassrootsHealth helped through the information on their website and facts on D; by using what you say and trying it out and seeing for myself it does work!!!

Mike (2021)

Vitamin D and Myasthenia Gravis

On February 4th, 2016, I was diagnosed with late-onset generalized myasthenia gravis with heavy bulbar involvement. My vitamin D level was 24 ng/ml. The first line treatment of prednisone and Mestinon did not work, so instead of continuing it and adding Imuran, I chose to go to alternative medicine. My NMD advised me to get my vitamin D level up to the high end of normal = 100 ng/ml. I was taking at the time 5,000 IUs per my neurologist RX. My level then was at 27 ng/ml.

After four months of weekly vitamin D injections of 75,000 IUs and oral supplements of 8,000 IUs daily, plus sensible sun exposure, my level got to 42 ng/ml. I started to feel better, had less severe myasthenia gravis symptoms and they occurred less frequently.

My vitamin D level for the last two years has been above 80 ng/ml (high of 97 ng/ml) and I rarely have myasthenia gravis symptoms. I am off prednisone and Mestinon, and the only prescription I take is low dose naltrexone. I take about 23,000 IUs of vitamin D with my breakfast and get regular sensible sun exposure. Thank you to GrassrootsHealth! I’ve watched many of your UCSD conference lectures that stimulated me to learn more about vitamin D. I just watched Carole Baggerly’s interview with Dr Mercola for 2011 and learned about your clinicals with vitamin D. If you ever do one for autoimmunity/myasthenia gravis I’m in.

B.M. (2019)

Vitamin D Helped with Fatigue

My last vitamin D level was 35 ng/ml, this was on 9/2/17. I take a supplement of 5000 IU per day. My level prior to this was 20 ng/ml; I had no energy. I felt like I could sleep all day. Afternoons were especially difficult, I would often come home from work at 5pm and go straight to bed. Only to wake up tired again the next day. Increasing my level to 35 has helped. However I still have the afternoon slump. I have changed my diet to whole food plant based which has also helped my fatigue.

D.A. (2018)

Make Sure You Are Getting Enough Vitamin D and Other Important Nutrients – Test At Home!

Having and maintaining healthy vitamin D levels and other nutrient levels can help improve your health now and for your future. Choose which additional nutrients to measure, such as your omega-3s and essential minerals including magnesium and zinc, by creating your custom home test kit today. Take steps to improve the status of each of these measurements to benefit your overall health. With measurement you can then determine how much is needed and steps to achieve your goals.  You can also track your own intakes, symptoms and results to see what works best for YOU.

Enroll in D*action and Test Your Levels Today!