Your immune system is complex. It consists of an intricate collection of cells and chemicals that perform complex functions to defend your body against invaders, including viruses, toxins, and bacteria. Keeping your immune system healthy is vital for preventing disease and infection. 

Eating a healthy diet, getting proper sleep, and moving your body every day are important steps for supporting your immune system. Research has shown that supplementing with certain vitamins, minerals, or other substances can also improve the immune response and protect against illness and infection. 

Here are 8 supplements that aid immune system functions:

Vitamin A 

Vitamin A is a fat-soluble vitamin that can be divided into 2 categories. Retinoids are found in animal sources and provide active vitamin A (ready for use in the body). Carotenoids are found in plant sources and include substances the body converts to vitamin A.

Immunity Benefits of Vitamin A:
  • Has anti-inflammatory effects
  • Is necessary in the body for detoxification of highly toxic substances
  • Plays a regulatory role in the immune responses in the body


Astaxanthin is a carotenoid (form of vitamin A) that is believed to be the most powerful antioxidant nature has to offer (6,000x stronger than vitamin C). 

Immunity Benefits of Astaxanthin:
  • Can handle multiple free radicals (up to 19) at a time (most antioxidants can only handle 1 at a time)

Vitamin C 

Vitamin C is a water soluble vitamin that cannot be produced by the body and therefore must be consumed by food or supplements. Vitamin C is not essential not only for proper immune function, but for many other essential body functions.

Immunity Benefits of Vitamin C:
  • Is a powerful antioxidant 
  • Benefits the immune system by increasing the number of white blood cells and interferons 
  • Supports the energy producing capacity of mitochondria
  • Can be taken in IV form for a higher concentration (Reduces the amount excreted through the urine because it enters the bloodstream and immediately increase serum levels in the blood)

Vitamin D 

Vitamin D is a fat-soluble vitamin that is provided from a few foods, primarily animal sources. Vitamin D is also produced by the body when sunshine comes into contact with the skin.

Immunity Benefits of Vitamin D:
  • Has anti-inflammatory effects
  • Is necessary for blood clotting
  • Can help protect against respiratory infections


Glutathione is a tripeptide composed of amino acids. It is produced in the body and is found in every single cell, but production levels often begin to decline after the age of 40.

Immunity Benefits of Glutathione:
  • Protects cells from damage by oxidation and free radicals
  • Stimulates the production of interleukin 1 and 2, which helps regulate the immune system
  • Helps recycle other antioxidants, such as vitamins C and E

NAC (N-Acetyl Cysteine)

Cysteine is a semi-essential amino acid that can be produced within the body from other amino acids. N-Acetyl Cysteine is the supplemental form of cysteine.

Immunity Benefits of NAC:
  • Is one of the building blocks of glutathione 
  • Is a powerful antioxidant 
  • Has anti-inflammatory effects
  • Breaks apart mucus in the lungs


Selenium is a mineral that is essential to optimal health in trace amounts. The amount of selenium found in food depends on the soil in which it was grown.

Immunity Benefits of Selenium:
  • Works with vitamin E as an antioxidant
  • Reduces heavy me
  • Plays a role in DNA repair
  • Is necessary for immune system function


Zinc is a mineral that is only needed in small amounts in the human body, but is a cofactor in over 100 enzymatic reactions. 

Immunity Benefits of Zinc:
  • Boosts immune defenses
  • Enhances biochemical actions of vitamin D
  • Aids in absorption of vitamin A
  • Needed for proper maintenance of vitamin E
  • Has anti-inflammatory effects
  • Is an antioxidant

We carry a wide variety of high-quality, filler-free, and efficiently absorbable supplement brands that go above and beyond what you can buy online or off the shelf. If you have questions about supplements you are taking or have been prescribed, our Wellness Team is here to help. 

This blog post is intended for informational purposes only and is not intended to diagnose or treat. It is important to note that some supplements can interact with prescription or over-the-counter medications and some may not be appropriate for people with certain health conditions. Be sure to talk with your healthcare provider before starting any supplements.

Stephanie Ritari, PA-C

Stephanie Ritari is a board-certified Physician Assistant who offers primary care for adults at the Functional Medicine of Idaho Meridian Wellness Center. She specializes in Internal Medicine and has spent the majority of her career in the field of cardiovascular disorders.

Stephanie has more than 15 years experience as a Physician Assistant in a variety of medical areas, including cardiology and electrophysiology. Holistic practices have long been a part of Stephanie’s lifestyle, with a particular focus on clean living and nutrition. She has embedded functional principles into her conventional medicine practice throughout her career. After watching family members struggle to find answers for their chronic illnesses, Stephanie became more interested in finding ways to take a root cause approach in her own practice. Wanting to provide a proactive, comprehensive, and preventative scope of care for her patients, Stephanie began studying functional medicine. In 2021, she joined Functional Medicine of Idaho, where she is able to provide evidence based, root cause medicine.

Stephanie earned her Bachelor's of Science in Exercise Physiology from the University of Montana and her masters in Physician Assistant Studies from Rocky Mountain College. She is currently working towards her certification with The Institute for Functional Medicine. 

In her spare time, Stephanie enjoys spending time with her husband, son, and dog doing outdoor activities including biking, hiking, and skiing. She also loves interior design and traveling, and is hoping to start her own garden in the near future.

Dr. David Musnick, MD, IFMCP

David Musnick is a board-certified medical doctor who offers in-person and telemedicine care from the Functional Medicine of Idaho Eagle clinic (coming soon). Dr. Musnick offers Functional Medicine, Sports Medicine, Functional Immunology, and Primary Care for adults and teenagers. He specializes in sports medicine, internal medicine, frequency specific microcurrent (FSM), scars, homeopathy, prolotherapy, and low-level laser treatments. 

Dr. Musnick is interested in getting to the root of underlying causes and factors that affect healing, including diet, sleep, exercise, stress, GI health, brain region health, toxins, hormones, infections, and electromagnetic fields (EMF). In medical school, Dr. Musnick spent a year studying nutrition. He has always been interested in the complex interrelationships of different systems of the body. Taking on challenges in the past, he created new treatment programs to heal the brain after concussion, treat chronic pain, arthritis, and tough SIBO and IBS cases. Dr. Musnick wants to help his patients achieve the highest level of health, vitality and function. 

After his internal medicine residency in Seattle, Dr. Musnick completed a fellowship in sports medicine where he became interested in helping patients get back to optimal musculoskeletal health and eventually back to their favorite activities. He quickly learned that many areas of the body were interrelated and started learning more about nutrition, supplements, and other facets of functional medicine. Dr. Musnick has more than 24 years of experience in Functional Medicine and achieved a very high level of both experience and expertise with many health conditions. He is also the author of the book, Conditioning for Outdoor Fitness, and helped in writing textbook chapters on arthritis and concussions.

Dr. Musnick received his Doctorate of Medicine from the University of California, San Francisco. He is certified through the Institute for Functional Medicine as an IFMCP. He also studied in the French school of Homeopathy. He is uniquely rare in that he teaches Frequency Specific Microcurrent (FSM) and how to integrate it with functional medicine. 

In his spare time, Dr. Musnick enjoys hiking, nature photography, cooking healthy food, mountain biking, and skiing.

IFM Certified Practitioner

Aaron Dykstra, DNP, FNP-C

Aaron Dykstra is a board certified Family Nurse Practitioner with a Doctor of Nursing Practice degree. He offers pediatric primary care, including well-child checks and acute visits, in the Pediatric Department of the Functional Medicine of Idaho Meridian Wellness Center.

Functional and alternative therapies were a part of Aaron’s life from a young age, and he has implemented these principles into his conventional medicine practice throughout his career. Aaron has more than 8 years of experience in a variety of medical disciplines, including pediatrics, obstetrics, mental health, and nutrition. He has practiced in rural health clinics in California and Oregon. For the last 5 years, Aaron has had a passion for working with children and implementing positive change through the family unit. Aaron joined the Functional Medicine of Idaho Pediatric Team in 2021. His enthusiasm for educating children and parents about living a healthy lifestyle allows him to provide preventative and acute care for infants, children, and adolescents. 

Aaron obtained his Bachelor of Science in Nursing at Brigham Young University. He earned both his Master’s of Science in Nursing and Doctor of Nursing Practice through the University of Arizona. He has obtained a Family Herbalist and Family Nutritionist certifications through The School of Natural Healing by Dr. Christopher. He is currently working towards his certification with The Institute for Functional Medicine.

Outside of work, you will find Aaron spending time with his wife and 5 kids, mountain biking, running, or camping in the backyard. Aaron is a big fan of Master Chef and enjoys cooking.

Nadia Kravchuk, DNP, FNP-C

Nadia Kravchuk is a board certified Family Nurse Practitioner with a Doctor of Nursing Practice degree. She offers functional pediatric primary care, including well-child checks and acute visits, in the Pediatric Department of the Functional Medicine of Idaho Meridian Wellness Center.

Nadia and her family immigrated to the United States in 1989 where they first settled in Oregon and then moved to Idaho in 2001. Complementary medicine practices were embedded into her lifestyle at a young age, and she has implemented these principles into her conventional medicine practice throughout her career. She has more than 15 years experience in a variety of medical environments, including emergency room, intensive care unit, pediatrics, obstetrics and gynecology, family practice, and aesthetics.

Nadia joined Functional Medicine of Idaho so that she can combine functional principles with the foundations of conventional medicine to address the underlying causes of disease and promote optimal wellness. As an avid gardener, beekeeper, and sustainable living enthusiast, she understands the importance and role of optimizing nutrition, sleep, physical, spiritual, and emotional well-being. She has a passion for pediatric functional medicine and understands that early recognition and interventions can correct imbalances, prevent chronic illness, and improve overall outcomes for children.

Nadia obtained her Bachelor of Science in Nursing at Northwest Nazarene University. She earned both her Master’s of Science in Nursing and Doctor of Nursing Practice through Frontier Nursing University. In 2017, she was the recipient of the HCA Excellence in Nursing Award. She is currently working towards her certification with The Institute for Functional Medicine.

Outside of work, you will find Nadia working on her urban homestead, hiking, foraging, camping, snowboarding, and spending time with her husband and her dog, Wolfy. She is also fluent in both English and Russian.