Tis the season – for colds, Covid and the flu! All joking aside, as we enter into the long-anticipated holiday season we must accept the probability that we may at some point feel under the weather. Luckily, acknowledging this allows us to preemptively continue or build some nice self-care routines which could help to minimize the duration or intensity of a sickness or perhaps prevent us from getting sick in the first place!
When it comes to the immune system – prevention is the name of the game. One of the most important things we can do to support our immune system is a healthy diet most of the time – remember we’re talking about the holiday season here; we’ve got to live a little too! Lucky for us our body doesn’t operate in extremes of healthy or not healthy. If we eat nutritiously the majority of the time, enjoying some fun-foods in moderation won’t set us back. Phew! We can have our pie and eat it too!
So, what should we be including the majority of the time? The first and perhaps most important thing to focus on is getting adequate Calories consistently. If we eat nutrient-dense foods but still fall short on our daily Calories, it’s like using the right gasoline for the car but letting it hover around E (and no, taking a supplement to make up the difference won’t cut it). Determining the proper number of needed Calories per day can be tricky since factors such as height, weight, age, movement/exercise, and any pre-existing medical conditions are taken into consideration. If you’re unsure of how many Calories you may need in a day, consult with a Dietitian to ensure you are getting enough (spoiler alert – it won’t be 1200 Calories or less per day!)
Ideally, to help us meet the majority of our daily needed Calories, we want to make sure we are getting enough fruits, vegetables, protein, carbohydrate, and fat sources. Consuming a good balance and variety of these, ensures that the immune system has the Calories it needs but that it has the micronutrient stores it needs to stay healthy and strong. While all micronutrients are helpful in maintaining health, some are exceptionally beneficial to help strengthen our immune system. These include Vitamins C, D, and the B vitamins as well as our minerals such as Selenium, Zinc and Iron.
As fruits and vegetables are loaded with micronutrients, they play a big role in helping support the immune system. Aim to get 5+ servings of fruits and vegetables per day. To incorporate some with extra-immune boosting micronutrients include leafy greens and legumes for B-Vitamins and mushrooms for Vitamin D. For sources of Vitamin C? If your mind went to citrus, you’re not wrong, but don’t forget to include some other fruits and vegetables that contain just as much if not more Vitamin C than citrus such as: yellow and green bell peppers, cantaloupe, parsley, cherries, kale, kiwis, broccoli, brussels sprouts, and/or strawberries.
You may know that protein is an important staple for a healthy diet or that it is something we want to eat when we’re already sick (chicken noodle soup anyone?) but just why is it so important? Dietary protein makes several crucial contributions to the immune system. First, it helps us to rebuild and repair our body from the natural wear and tear of our day-to-day, or to help us repair any initial damage from a cold or flu trying to settle in. If you feel a cold coming on but then start to pick up the next day – protein almost definitely played a role. Protein also helps us to produce antibodies – which I personally like to think of as the immune system’s front-line soldiers. Protein also helps us to make something called L-Glutathione which aids in repairing damaged cells. Did I mention the variety of immune-boosting micronutrients that dietary protein provides!? Iron, Zinc, Vitamin D, and B-Vitamins can all be found in protein sources! For example, red meat provides an abundance of all of the aforementioned micronutrients. When choosing animal proteins, aim for lean sources, ideally organic, free-range and grass fed (as you are able to, but also keeping in mind that any red meat is better than none considering the nutrient density). Who knew that seasonal beef stew could be so immune boosting?
Our fat sources also support the immune system by providing a rich source of Calories (aiding us in reaching those daily caloric needs,) and providing immune-boosting micronutrients. For fat sources rich in B vitamins, include avocado, egg yolks, sunflower seeds, nuts, and fatty fish such as salmon (which also counts as a nice protein source).
Carbohydrates are the bodies’ preferred fuel source and provide our main source of dietary fiber. Sources include: starchy vegetables (such as potatoes and butternut squash), non-starchy vegetables (such as zucchini and salad greens) fruits, beans/legumes, and grains such as quinoa, rice, crackers, oats, cereals, pastas, and breads. What does fiber have to do with the immune system? Fiber is the food source for our good-gut bacteria which live in our gastrointestinal tract. Since it is estimated that at least 70% of our immune system is located in our gastrointestinal tract, we’re learning that our good-gut bacteria not only come into contact with the immune system but they can have a strong and positive impact. Research suggests that a healthy gut microbiome not only positively impacts the immune system but that these good-gut bacteria are actually responsible for educating the immune cells on how to fight viral infections (aka colds, Covid, and the flu)! So while fiber is often attributed for aiding in bowel movement regularity we’re finding its positive impact on the immune system to be absolutely essential. This season, aim for some cozy carbs rich in fiber like rolled oats for breakfast, beans in your chili, and/or protein pasta sheets for homemade lasagna – your gut and immune system will thank you!
While there is no replacement for a nutrient rich diet, it never hurts to include a good Multivitamin. This can fill in any nutritional gaps we may experience, helping to ensure we feel our best. A good example of this is Vitamin D. While we may ingest some through foods it is easy to fall short in the colder darker months of fall and winter. When selecting a Multivitamin, aim for one that is Certified NSF (for National Sanitation Foundation) or GMP (for Good Manufacturing Processes) to ensure the quality of what is being ingested.
Another trick to boosting our immune system is by making sure we help our body detoxify. It does a great job of this naturally via: sweat, urination and yes – bowel movements, but there are some things we can do to help these functions operate as smoothly as possible.
Sufficient fluid intake is crucial for our ability to sweat, urinate, and have regular bowel movements. As a general rule of thumb, you can get an estimation of your daily fluid needs in ounces by taking your body weight in pounds and dividing it in half. For example, if someone weighs 200lbs, their estimated fluid needs per day would equal 100 oz. (before accounting for additional fluid loss from things like exercise). A good way to check your hydration is to monitor your urine color. You want it clear to very lightly yellow, like lemonade. Anything darker like apple juice indicates inadequate hydration. And remember – fluids do not have to come strictly from water to count! Soups, high water fruits and vegetables, and herbal teas all help you meet your fluid needs.
Adequate fiber intake is another way we can help our body to detoxify. Including fiber rich food sources in the diet tend to be more effective than relying on fiber supplementation. Good dietary sources of fiber include: fruits and vegetables with the skin intact, nuts and seeds, beans and legumes, and whole grains. Fiber needs can vary throughout the lifespan and between genders. More information on fiber can be found here.
Another great way to help our body detoxify is by including regular movement/exercise, especially something that helps us – you guessed it – sweat! Regular movement and exercise, especially forms of appropriate cardio have been shown to aid in consistent bowel movements. Anything from a brisk walk, hike, spin-class, jog/run, swim, heated yoga, or even a sit in a sauna can be great options. Always clear your intended activity/movement with a health professional before incorporating something new, especially if you have one or more medical diagnosis.
Individuals struggling with disordered eating should check with their Dietitian to ensure added movement is safe and will be recovery-promoting rather than detrimental. Another less known way to help detoxify is to incorporate more cruciferous vegetables into the diet. Yes, that’s right, cruciferous vegetables! Leave the expensive supplements and low-Calorie juicing diets behind (I’m convinced a true hater of joy concocted the juice-cleanse trend). Cruciferous vegetables help our liver to detoxify because they contain compounds that aid in our detoxification pathways. They also aid us in activating our B-Vitamins more efficiently which not only boosts our immune system but can help us to feel more energized. Examples of cruciferous vegetables include cauliflower, broccoli, radishes, cabbage, turnips, brussels sprouts, and more!
So, we’ve reviewed what to include in the diet but is there anything to avoid? While there is nothing to avoid 100% of the time, some foods are better enjoyed in moderation. The 2 big ones that come to mind when discussing immunity? Alcohol and added sugars. These are a little inflammatory by nature so an excess volume can cause more body-wide inflammation and cell damage which in turn weakens the immune system. The CDC recommends that men limit alcohol to 2 drinks or less per day and 1 drink or less per day for women. So, enjoy that glass of wine at Thanksgiving, that Christmas morning mimosa, and/or a glass of champagne to ring in the New-Year! Added sugars – now this is a hot-topic! Added sugars are inflammatory by nature and in excess can have a negative impact on the immune system. This doesn’t mean we have to avoid them completely but aiming for a limited amount per day can be beneficial. The CDC currently recommends keeping added sugars to 10% or less of total daily Calories. The AHA recommends no more than 3 Tablespoons of added sugars per day for men and no more than 2 Tbsp of added sugars per day for women. Preventative medicine practices recommend aiming for 1 Tbsp of added sugar or less per day. Yes – this information is conflicting and that can feel confusing. Do the best you can and if you notice some of your staple-items are higher in added sugars, consider a swap you may equally enjoy. This will not only help your immune system but will help you to feel your best on the day to day! Does this mean we should strictly watch our sugar intake on holidays such as Thanksgiving, Christmas, or New Years? – No! Again, live a little. A couple of holidays here and there will not make or break our bodies’ immune system just as eating nutritiously for only a couple of days here and there wouldn’t support our body’s health sufficiently.
You can chat with your Dietitian to determine if your current sugar level is appropriate. If you are someone working on more food freedom, especially in eating disorder recovery, this advice may not be applicable to you. You may be at a stage in your recovery where you need to incorporate more higher-sugar items to let go of the eating disorder/disordered eating- this is okay! Remember, our total body health is about our physical and mental wellbeing and having an eating disorder is far worse for you than having more sugar than the CDC recommends. You can always apply the other advice in this article to help boost your immune system!
One of the last but most simple things we can do to help boost the immune system this season is adequate sleep and relaxation. Consistent poor sleep hygiene weakens the immune system, provides less recovery time from the day to day grind, and causes our body to whip through our micronutrient stores at a quicker rate to compensate. Stress, although an unavoidable fact of life, also can do a number on the immune system. When our body feels as though it is in a constant state of stress it reverts to “fight or flight mode”. While this is a super helpful feature when trying to outrun a tiger, it’s not so helpful when trying to navigate the holiday season for weeks on end. Stress can negatively impact sleep quality, digestion, bowel movements, mental health, and the needed energy for other forms of self-care such as exercise or meal prepping. While it’s impossible to avoid stress completely this holiday season (we don’t live in a bubble after all!) aim to incorporate some self-care strategies as you’re able to. This could look like getting to bed earlier, chipping away at your holiday shopping list in advance (even if it’s just planning on what item to buy or make), incorporating some time for movement/exercise you enjoy, and/or enjoying a pastime that helps you unwind (vs social media scrolling). Remember, it is OK to say no to invitations this holiday season – feeling burnt out and run down takes a mental as well as physical toll.
I hope after reading this you have some more tools in your tool box for boosting your immune system this holiday season. Special occasions are always more enjoyable when we feel we have the energy and health to truly be present. Wishing you and yours a happy holiday season and a happy New Year!
