A healthy immune system grows ever more important as we age, and immune status is closely associated with nutrition, exercise, quality sleep and stress reduction. There may be certain population groups who will benefit from supplementation to optimise their immune system such as the elderly, athletes, and people with compromised immune systems and chronic health conditions. When supplementing it is also important to take into consideration any use of medication as some nutrients and supplements can affect the absorption, strength and interaction of the drug and as a result have an adverse effect on the individual.
Before starting any supplement regime, it is important to talk to your doctor or health professional. In addition to the above lifestyle measures, there are some supplements that can power up your immunity and are best to take year-round, and there are other supplements that are helpful specifically during cold and flu season when you’re battling symptoms associated with a low immunity:
Supplementation that may assist with the prevention of colds and flu’s:
- Age and gender-specific multivitamin– this acts as an insurance policy and safety net. Consuming a daily comprehensive multivitamin that has been formulated to provide key nutrients for your age and gender can provide support to your immune system by boosting antioxidant levels, protecting cellular DNA damage and reducing free radical damage. Supplementation with a multivitamin can enhance immune function and is the simplest way to ensure sufficient levels of these various vitamins and minerals.
- Vitamin D– No other supplemented nutrient has been as extensively studied as vitamin D. Many studies have shown that adults (and children) with higher vitamin D levels contract substantially fewer cold, flu, and other viral infections. Vitamin D supresses pro-inflammatory markers and boosts the activity of antimicrobial markers in immune cells.1,000 – 5,000 IU daily for most adults is safe and effective for the prevention of flus, colds, and other diseases.
- Omega-3 fatty acids (fish oil)– Is a powerful anti-inflammatory agent and increases the activity of white blood cells that help fight off infection. Omega-3 is also needed to help vitamin D work in an optimal manner, which also helps prevent vitamin D deficiency. Adults may consume a high quality fish oil supplement providing at least 1400 mg EPA and 1000 mg DHA daily.
- Probiotics– Over seventy percent of our immune system is controlled by what occurs in the gut.Our gastrointestinal tract relies on live bacteria to help support a healthy immune response. These probiotic bacteria help prevent foreign bacteria and allergens from passing through the intestinal wall and are important to support and strengthen the overall health of the intestinal immune system. Probiotic consumption is particularly important after the use of antibiotics. A quality probiotic containing at least lactobacillus and Bifidobacterium, consumed once or twice, daily as per instructions will suffice.
Supplementation that may assist during a cold, flu or suppressed immune system:
- Zinc– 50mg per day may be an effective preventative for a cold/flu worsening. Zinc helps to boost the activity of antioxidants and thus reduce oxidative stress. Zinc deficiency has been linked to impaired immune function and so too has high levels of zinc intake.
- Vitamin C– is an important component of the immune system and antioxidant defence. It helps prevent the production of free radicals and reduces DNA damage to immune cells. Supplementing with 1,000 – 5,000 mg vitamin C, daily may assist with reducing the severity and duration of a cold/flu.
- Antioxidants– vitamin A and E – both powerful antioxidants to reduce inflammation and free radical damage during a cold/flu.
Are there any risks in taking too many supplements or high doses?
For any supplement there is a recommended upper limit of consumption as too much of a nutrient may cause toxicity. Every nutrient has a different level of toxicity and symptoms associated with it. Therefore, it is important you do not excessively exceed the recommended daily intake of some nutrients.
Dosage instructions on supplements are generally safe and always have warnings for particular nutrients that may have contraindications. For example, the recommended daily amount of vitamin A, from all sources is 700mcg retinol equivalents for women and 900mcg retinol equivalents for men. When taken in excess of 3,000mcg retinol equivalents, vitamin A can cause birth defects. Another example is vitamin K. The consumption of this nutrient should be strictly monitored in those on anticoagulant medication such as warfarin.
You should always read the label and use only as directed. If you are unsure, ask your doctor or health professional.
Are there any nutrients that may harm our immune system?
Omega-6 fatty acids – These oils are predominantly consumed through plant-based oils e.g. safflower oil, sunflower oil, cottonseed oil, corn oil etc. The problem with these oils is that they are ‘pro-inflammatory’, which are associated with and contribute to a suppressed immune system and an increased risk of inflammatory diseases such as cardiovascular disease, type 2 diabetes, obesity, autoimmune disease, asthma and cancer to name a few. Omega- 3 fatty acids on the other hand are ‘anti-inflammatory’, which help reduce risk of inflammation in the body. The problem with the Western diet is that the omega-6:omega-3 ratio is too high, resulting in an over consumption of omega-6’s and not enough consumption of omega-3’s, potentially raising the risk for a range of diseases.