by Dr. Charlotte McKnight
It’s my favorite time of year: apple picking, pumpkin spice, changing leaves and back to school! Autumn is here, but with it, so is cold and flu season. If you have school-aged children or little ones in daycare, you know it can feel impossible to prepare for the germs that are sure to begin their seasonal parade through your home. While good hand washing, covering your cough and staying home when you are sick can help to contain the bugs that make us sick, is there anything that can keep you well?
We know the immune system is a complex machine. It requires certain vitamins, minerals and macronutrients to build up all the components of our immune system and keep them functioning smoothly. Unfortunately, packing those building blocks in via diet or supplements doesn’t always have the intended effect, so here is what you need to know when you’re browsing the aisles of the pharmacy.
The most promising data is in studies of patients with deficiencies in certain vitamins or minerals. Even in people with minor deficiencies, these supplements may make a difference in severity, duration, and prevention of certain illnesses. The limited diet of picky eaters can certainly contribute to these deficiencies. Additional contributors include increased stress, pollution and simultaneous or back-to-back infections, as these things can increase our requirements for the building blocks of our immune system.
Of the available immune support supplements, Vitamins C, D and Zinc seem to have the most supportive medical evidence of improving both the development and function of the immune system. Other vitamins and minerals have some positive data but not enough to waste your time or money on, as they likely are not as beneficial for otherwise healthy people. There are some promising studies regarding probiotics in helping with the immune function of the gut and possibly even beyond, with some studies demonstrating a link to probiotics and systemic immune health. However, these outcomes are not consistently reproduced and likely warrant more research.
How do you increase these vitamins and minerals in your body?
The best way is to optimize your nutrition through your diet. Vitamin C can be found in citrus fruits like oranges and grapefruit, cruciferous vegetables like broccoli and cauliflower, and dark green leafy veggies like spinach and kale. Certain foods like milk, juices and cereals are fortified with Vitamin D. Zinc is common in beans, lentils, nuts and eggs. If you are picky or avoid certain foods for health or religious purposes, you might consider a supplement, but remember that more isn’t always better.
Many of the vitamins and minerals that are important for our immune system can make us sick when we take too much. The most common side effect is GI upset. Too much Vitamin C can increase your risk of kidney stones and taking too much Zinc can have the reverse effect and cause impaired immune function. Because our daily value of these nutrients is dependent on age, whether you’re pregnant or nursing, and health status, check with your doctor before choosing a dose for yourself and your family. Remember some supplements can interact with certain types of medications, so be sure they are safe to take together.
Ultimately, the way to improve immune health is through a healthy, varied diet. While Vitamin C, D and Zinc have the most supportive medical evidence, there is no overwhelming literature to suggest that these will make a big difference in healthy people outside of dietary recommendations. Although safe at certain levels, overdoing certain supplements can cause side effects and they may react with medications you are already taking. The real secret to a healthy cold and flu season? It’s the same for a healthy life: a healthy diet, regular cardiovascular exercise, a good night’s sleep, stress management (think mindfulness, deep breathing, yoga) and don’t forget your yearly flu shot!