A recent study on frontline healthcare workers found that a plant-based diet reduced the odds of severe COVID19 by 73%, and a pescatarian diet by 59%. On the other hand, those following a low-carb, high-protein diet - were almost 4x more likely to experience moderate-to-severe infection. Granted, this is a correlation, not causation, and there are many limitations e.g. accuracy of diet recall/surveys, so we need more robust research to make definitive conclusions, and by no means is anyone saying a plant-based diet can 'prevent' you from catching it - BUT it does send an important message that what is on your matters to your health!
What you eat can either impair or enhance your immune system, and you cannot out supplement a poor diet... sorry to say.
The No1 thing in our diet that impairs is REFINED SUGAR, and this is the number 1 thing I'm watching in my kids as they head back to school. Studies have shown that high blood sugar can hinder the soldiers in our immune system e.g. Natural killer cells, which are our first line of defense against pathogens. This is why people with diabetes are at higher risks of infections, and perhaps why kids seem to catch a cold/flu so much more easily after a birthday party.
In particular, studies have shown that elevated blood sugar can increase the risk of complications for Covid19 e.g. cytokine storm, blood vessel damage, and multi-organ failure.
Sadly, 7 in 8 Americans have poor metabolic health (e.g. high blood sugar, cholesterol, blood pressure), and most don't even know it. In my clients, I see so many people with red flags - an elevated fasting blood sugar, or HbA1c but because they are not in the diabetic range 'yet', their doctors say no action is needed.
An important window of opportunity is missed if we just sit and watch those numbers climb into the 'diagnosis' range. We don't get diseases overnight, there is always a gradient of derangement that starts way before we even get a disease.
The 'pre-diabetes, 'pre-disease stage is amenable to lifestyle changes, and if you are interested in optimizing your metabolic health - join me at the FREE Metabolic Makeover Summit on August 30th.
Ok, back to some key action steps on how to optimize your diet for immune health.
1. Reduce refined sugar intake.
This includes white baked goods (processed flour is absorbed rapidly and leads to a high blood sugar soon after consumption), cereal, granola bars, and hidden sources like yogurt, sauces, drinks. Did you know a Starbucks frap has around 12 tsp of sugar?
I am not, however, talking about whole, fresh, fruits, which do not spike your blood sugar (unless you have insulin resistance, in which case, work on reversing that first). Fresh fruit has lots of fiber which holds onto and ensures a more controlled release of sugar, not to mention the antioxidants which our immune system needs to function optimally.
In fact, many of the flavonoids in fruits have been found to be beneficial (I have a whole section on this later).
Now that we've talked about what to avoid, let's talk about how to optimize:
2. EAT MORE PLANTS - As the recent study showed, a plant-based diet has been associated with a significant reduction in the risk of severe COVID19.
Also, fiber and polyphenols are essential for our gut microbiome to thrive, and we all know that gut health is crucial for immune health. In fact, studies have correlated poor gut health and an unhealthy balance of bacteria in our gut with more severe covid outcomes. So, ensure you have a healthy gut microbiome by feeding your friendly gut bugs lots of plants.
Each type of plant feeds a specific subset of gut bacteria, so the more plants you eat the more gut microbiome diversity, the more diverse your gut microbiome, the better your gut health. The better your gut health, the better your immune health.
If you need help getting more plants into your diet, check out my ebook How to Eat More Plants, filled with tips and tangible steps to incorporate more plants into your diet with 25+ yummy recipes. I also have a e-cookbook with 40+ delicious recipes (Plate For Health) and meal prep ideas to help you get delicious yet nutritious plant-based meals on your plates.
3. GET THOSE FLAVONOIDS IN
I do believe these are some of the reasons why a plant-based diet has been observed to be associated with less severe COVID19.
There are many different flavonoids but the one of note is quercetin - found in green tea/matcha, apples, onions. If you are taking zinc, you might be interested to know that quercetin actually helps zinc get into the cells where it needs to be to work.
Here are the practical steps of how I am translating what I'm reading in the research to my everyday life:
I prefer to get most of these from food sources and only supplement on a short stint if I need to e.g. when I start to feel unwell, and I usually would stop the supplement after a few days. I have personally seen side effects from over-supplementation, so please note that more is not always better with the supplements, and if you do take them on a prolonged basis, you must check the levels with your doctor.
a) Pique Daily Immune - this is a liposomal form of vitamin C + elderberry. (discount code platefulhealth). The big advantage of this one is that it is shelf-stable and does not need refrigeration - so I always take this when traveling. If you have autoimmune diseases, elderberry might not suit you - check with your doctor. More on elderberry and how to use it below.
b) Quicksilver liposomal Vitamin C - I use this one when I don't want the elderberry. Another one I like is the liposomal Vitamin C from Seeking health (discount code DRVIVIAN) - both of these need refrigeration.
c) Zinc AG by Metagenics
d) Vitamin D and Omega 3 from Vivolife (discount code platefulhealth)
e) Tasha rose Victory elixir - I give this to my kids every day right now (discount code platefulhealth) . I also have her Cough syrup on hand during the fire season to support our lung health and if we do have the sniffles.
f) I don't take probiotics, but I eat fermented foods daily.
Homemade remedy for gargling: ½ red onion, 2 tbsp apple cider vinegar, pinch of cinnamon, 1 cup water. Blend it all up. Strain through a cheesecloth or nut milk bag, and gargle with the liquid - I do not suggest swallowing it as it does not taste good and also may worsen any reflux/gastric issues if you have it. Rinse your mouth out and try not to let the mixture come into contact with your teeth too much due to the acidic vinegar. (ps. if you have any open wounds/mouth ulcers this may burn so be careful) - I gargle with this 3-4 times a day, at the first sign of illness e.g. sore throat.
Elderberry has been shown in studies to shorten the duration of the common colds. However, it has not been shown to do the same for Covid. In fact, there is controversy on whether it may even 'worsen' the inflammatory phase in Covid-19 known as the cytokine storm.
Let's back up and break this down a little more. Two main processes are thought to drive the pathogenesis of COVID-19:
1. Early in the clinical course, the disease is primarily driven by the replication of the virus SARS-CoV-2 and infection (this usually lasts 3-4 days).
2. Later in the clinical course (day 3-11), the disease appears to be driven by a dysregulated immune/inflammatory response to SARS-CoV-2 that leads to tissue damage. i.e. the virus is not causing the damage - our own, runaway immune system is.
Based on this understanding, it is logical then that things which directly target the virus and replication e.g. zinc, may be more appropriate early in the course of the disease, while anti-inflammatory compounds are likely to be more beneficial in the later stages. (Just like dexamethasone, an immunosuppressant medication, is only recommended for use in the later stages and certain clinical settings).
The idea that elderberry may contribute to the cytokine storm was based on 1 study and the risk is more theoretical than proven. It is thought that because elderberry can increase the release of a cytokine called IL-1B, which is a part of the inflammatory reaction to COVID-19, that it may worsen the cytokine storm.
The jury is still out, and I'm recommending that you get your tailored advice from your own doctor if you do want to use it. The way I am using it now is that I take it several times a week to build my defense. However, at the first sign of symptoms, I plan to stop.
Obviously, nothing has yet been proven to prevent or treat Covid19, and we don't yet fully understand the cytokine storm or how to treat or prevent it. It appears that there may be a genetic component to this too. However, since chronic inflammation is a contributor to OTHER chronic illnesses anyway, it makes sense that we take steps to reduce our baseline level of chronic inflammation while we wait for more definitive data to come through.
a) stress reduction (breathwork, meditation, yoga, self-care)
b) sleep (yep I'm going to keep talking about sleep, it IS that important)
d) metabolic health and good blood sugar control - what we eat is more important right now than ever
e) Safe sun exposure/nature.
f) plant-dominant and a nutrient-dense diet, anti-inflammatory omega 3's.
g) doubling down on those flavanoids and getting lots of herbs, spices, teas - quercetin, hisperidin, rosemarin etc which are powerful antioxidants from tea, citrus, rosemary, that quench inflammation and has also been proposed to act as zinc iotonphores, helping zinc to get inside the cell where it may potentially have inhibitory effects on the virus. Flavanoids are only found in the plant kingdom and that's why I promote a plant-diverse diet, including tea and herbs. Turmeric is another favorite and something I try to incorporate daily to help with inflammation.
h) Reducing inflammatory foods: refined sugar, processed foods, fried foods, and inflammatory oils like vegetable/sunflower.
MOVE your body. Exercise can help our lymph flow and support our immune system. Note, rigorous and over-exercising can cause a temporary dip in your immunity - so ditch the heroic overtraining, and aim for moderate activities that are suitable for your fitness level, preferably in nature if possible. Forest bathing, aka walking in the woods, has been found to boost Natural Killer cell function (these are the soldiers in our immune system acting as the first line of defense).