“Humanity has but three great enemies: fever, famine, and war; of these by far the greatest, by far the most terrible, is fever.” Sir William Osler.

We have all been hearing about what can boost or prime or improve our immune system in the fight against “you know what”. The news changes daily and it can be frustrating to know, what to do, who to listen to, who to ignore, and ultimately what is the best course of action. The situation is that nobody knows fully how this new Coronavirus will develop. There are presently 6 strains of the virus according to sciencedaily but this could change tomorrow. There is still no vaccine for SARS or MERS, the other two coronaviruses that emerged this century. The culprit of the Spanish Flu of 1918 which was estimated to infect 50% of the world population, kill 100 million people or one-fifth of the earth’s population, was only discovered in 1997 when the body of a woman who died of the flu around the time, was dug up in Alaska. Her body was preserved by ice and thus made it possible to get DNA samples and therefore discover where the flu had originated from. It was only in 2005 that the answer to the great killer was published, that it had come from bird flu.

The 1918 influenza pandemic killed more people in a single year than the bubonic plague killed in a century.

Because they had no idea what hit them in 1918, they had no idea how to react, so there was no vaccine, it simply ran out of people to infect, the people that survived were immune. If the Spanish Flu was to reemerge today, just like SARS and MERS or the even worse bird flu – ‘H5N1’ which emerged in Hong Kong in 1997 and killed 60% of its victims compared to 1918’s “mere” 20%, there is no cure, no vaccine.

N5NI – “A disease of biblical proportion.”. – Mike Ryan, founding member of the Global Outbreak Alert and Response Network at the World Health Organization.

So the advice that we are given in relation to protecting ourselves from COVID-19, is pretty much the same as we’ve been receiving in order to prevent or avoid all other types of illnesses, even severe ones, i.e. help your immune system to help you. It’s a no-brainer really but obviously can be frustrating for people who on a daily basis wait for the “one” bit of news, that one cure, that one vaccine, the magic pill.

Vitamin C has been popping up and then popping down in either a way to prevent or treat or none of the above since all this started. Dr. Andrew W. Saul, an international expert on vitamin therapy said in February “people are dying needlessly of coronavirus”. In a Facebook post, he said high doses of Vitamin C can slow down and even prevent the virus. But if you look at the famous American CDC,  Centre for disease control, you won’t find a mention anywhere for Vitamin C, and strangely enough, none for Vitamin D either as a preventative.

I always remember being a kid and if I was ever sick or I got a cold, my mum would make a delish orange and honey drink, and I’m sure you have similar stories. So we know the vitamin is used to treat colds, it doesn’t seemingly cure them but it can reduce its longevity. We know it’s a major antioxidant, which means that it stops or reduces damage done to cells by “free radicals” which are produced during the digestion of food. These free radicals can go on to cause all types of illnesses including the big 3; cancer, heart disease, and diabetes. Studies also show that consuming more Vitamin C can boost antioxidant levels by 30%. What’s also interesting is that without Vitamin C, the body cannot make collagen, the most abundant protein in the body, it basically keeps us together, as a support structure and gives the skin elasticity and strength. Some types of collagen are gram for gram stronger than steel! Moreover, Vitamin C has been noted in the area of cancer treatment and also Sepsis. In the case of both, there have been tests done to prove that increasing levels of the vitamin revealed a reduction in mortality.

So how could taking extra Covid-19 help prevent or help treat the virus? Well, we need to go back to the reason it’s used to treat Sepsis. Dr. Malcom Kendrige, in his weekly blog, explains the theory but reminds us that some scientists still disagree that Vitamin C protects us against Covid-19. His point though is that apart from respiratory disease, cardiovascular complications due to getting the virus are appearing as a risk because the membrane that lines the heart (endothelium) can also be attacked. Something that can protect this lining is Vitamin C. Thus Dr. Kendick strongly supports the use of Vitamin C. 

So how much should we take on a normal basis? According to the Office of Dietary Supplements (ODS)

  • 90 milligrams (mg) for males
  • 75 mg for females
  • 85 mg when pregnant
  • 120 mg when breastfeeding
  • an additional 35 mg for people who smoke

One report suggests that 200mg is the optimal dosage to take. However, as an extra protective measure against Covid-19, it has been recommended by Professor Paul Merrick, lead clinician at the East Virginia Medical School to take up to up to 1000mg a day. Your question immediately might be, can you take too much? Vitamin C is one of the least toxic substances known so even though too much vitamin C is unlikely to be harmful, super doses up to 2000g of supplements might cause, Diarrhea, Nausea, Vomiting, Heartburn, Abdominal cramps, Headache, Insomnia. 

So apart from oranges, where do we find Vitamin C? 

Food Serving size Milligrams (mg) per serving Percent of 90 mg daily value (DV)
1 Guava, raw 1 cup, raw 377
2 Sweet red pepper, raw 1 cup, raw 190
3 Tomato juice 1 cup, canned 170
4 Orange juice 1 cup 124
5 Sweet green pepper 1 cup, raw 120
6 Hot green chili pepper, raw 1 pepper, raw 109
7 Oranges 1 large fruit 97.5
8 Strawberries 1 cup, sliced 97.6
9 Papaya 1 small fruit 95.6
10 Pink grapefruit juice 1 cup 93.9
11 Broccoli 1 cup, raw 81.2
12 Pineapple chunks 1 cup, raw 78.9
13 Potato 1 large vegetable 72.7
14 Brussels sprouts 1 cup, raw 74.8
15 Kiwifruit 1 fruit 64
16 Mango 1 cup, raw 60.1
17 Cantaloupe 1 cup 57.3
18 Cauliflower 1 cup, raw 51.6
19 Lemon 1 fruit 44.5
20 White grapefruit ½ medium fruit 39

I know what you’re thinking, to reach 1000mg a day just with food could be testing. So an option is to supplement. I take a supplement of 500mg a day on top of what I get from my diet and I’m happy with that quantity. 

To summarise, it will be a long time until we know everything about Covid-19 and more research into the effects of high dosage Vitamin C as prophylaxis or as treatment needs to be done. Looking after your lifestyle which includes your diet, will help your immune system to protect you against not only Coronaviruses but other major illnesses is still as important as ever. When my clients ask me about extra protective measures against Covid-19, one of them I suggest is extra Vitamin C in their diet. 

Vitamin C under a microscope.



Book: How to survive a pandemic. Dr. Michael Gregor.