Surefire Ways to Boost Your Immune System
Article by: Consultant Dietitian Kong Wen Yuan
A healthy diet is crucial for keeping the immune system strong enough to fight viruses, fungi, parasites, and bacteria. A well-functioning immune system defends against harmful organisms, while a weak immune system makes infections more likely and severe. Inflammation is a part of the immune response, but if it’s excessive, it can damage tissues and cause problems. [2]
Boosting the immune system can be achieved through a balanced diet. Essential nutrients like vitamins A, C, E, K, zinc, iron, and protein support immune function. Eating a variety of foods rich in these nutrients helps strengthen the immune system.
The following foods may help to boost our immune system:
1. Citrus Fruits
Citrus fruits, such as oranges, lemons, limes, tangerines, and grapefruits, are packed with vitamin C, flavonoids, and fiber. These nutrients help protect blood vessels, reduce inflammation, and improve gut health. They also play a key role in preventing diabetes, cancer, and neurological diseases. [1]
Vitamin C supports the immune system by aiding tissue repair and keeping skin and blood vessels healthy. As an antioxidant, it helps prevent cell damage and boosts immune function by increasing white blood cell production. Studies show that taking 1 gram (1,000 mg) of vitamin C daily can reduce the flu’s duration by 8% in adults and 18% in children. [3]
2. Kiwi
Kiwi, also known as kiwifruit or Chinese gooseberry, is a great source of vitamin C and also contains vitamin K, potassium, folate, fiber, carotenoids, and polyphenols. These nutrients support the immune system and help protect against colds and flu. Kiwi can also safeguard DNA from damage and has anti-cancer properties.
Additionally, kiwi seeds have alpha-linoleic acid and omega-3 fatty acids, which may help maintain a healthy heart rhythm and improve blood circulation, reducing heart disease risk. Regularly eating kiwi may also help lower blood pressure, potentially reducing the risk of strokes, heart attacks, and other heart-related issues. [4]
3. Ginger
The health benefits of ginger have been touted for centuries, demonstrating its ability to help treat colds and sore throats due to its anti-inflammatory, antibacterial, and antioxidant properties that combat illness. Additionally, ginger is used to reduce nausea and aid digestion.
Some studies show that ginger can speed up gastric emptying, making it effective for bloating, indigestion, and stomach aches. Additionally, ginger can lower LDL cholesterol levels, reduce menstrual pain, and improve brain and heart health. Moreover, the International Journal found that ginger supports the immune system and may be effective in preventing cancer. [5]
4. Garlic
For centuries, garlic has been used to prevent colds, flu, heart disease, and high cholesterol. Beyond its flavor in cooking, fresh garlic has antiviral, antifungal, and antibacterial properties. It contains allicin, an immune-boosting compound released when garlic is chopped or crushed, and antioxidants that help fight infections and support immune function. Garlic can also help lower blood pressure and slow artery hardening.
A study in Clinical Nutrition found that garlic extract improves the immune system in obese adults. The group taking 3.6 grams of aged garlic extract had lower inflammation and better immune cell distribution compared to a placebo group. [6] Another study showed that participants taking 2.56 grams of aged garlic extract had fewer and less severe symptoms compared to those receiving a placebo. [7]
5.Turmeric
Turmeric contains a compound called curcumin, which gives it a deep yellow color and is credited with most of its potent health benefits. Specifically, curcumin appears to have the ability to modulate the immune system by activating certain immunity-related cells and dampening the effect of specific pro-inflammatory compounds, thereby boosting immunity.
While turmeric is a flavorful and nutritious spice, it has also traditionally been used in Ayurvedic and Chinese medicine to treat inflammatory conditions, skin diseases, wounds, digestive ailments, and liver conditions. Additionally, studies support turmeric for pain relief, and its anti-inflammatory properties can reduce joint discomfort in arthritis sufferers. [8,10]
6. Salmon
Salmon is a nutrient-dense food primarily known for being a rich source of omega-3 fatty acids, which promote a healthy immune system and facilitate faster recovery. [9] Additionally, the vitamin D in salmon plays a crucial role in the natural antimicrobial response, helping the immune system function at full capacity.
Additionally, B vitamins such as B2, B6, and B12 support T cell function by controlling inflammation. Selenium, an antioxidant found in salmon, helps reduce oxidative stress in the body, thereby boosting immunity and reducing inflammation. Furthermore, salmon contains minerals such as zinc, iodine, magnesium, calcium, phosphorus, iron, and potassium.
7. Spinach
Spinach is one of the best leafy greens available, highly nutritious and packed with a variety of vitamins and nutrients. It contains high doses of vitamin A, vitamin C, and vitamin E, which help fight infections and replenish blood cells, thereby strengthening the immune system. Additionally, spinach is particularly rich in vitamin C, which is beneficial for heart health.
Additionally, spinach contains other nutrients that contribute to cardiovascular health, such as beta-carotene, folate, magnesium, and potassium. These nutrients work together to prevent cholesterol oxidation and reduce levels of the amino acid homocysteine. Furthermore, the vitamins and minerals in spinach also help improve skin health, eye health, bone health, and muscle health, and possess cancer-fighting properties. [10]
8. Broccoli
Broccoli is an excellent ingredient to incorporate into your diet. It is packed with vitamins and minerals, including vitamins A, C, E, K, potassium, magnesium, folic acid, and a variety of antioxidants. The combination of vitamin C and antioxidants works effectively to support the immune system.
A study found that sulforaphane, a chemical in broccoli, activates a group of antioxidant genes and enzymes in certain immune cells. These then combat the harmful effects of molecules called free radicals, which damage body cells and cause disease. In fact, studies show that eating more broccoli can help prevent colds and flu. [10]
9. Almond
Almonds are rich in vitamin E, a powerful antioxidant that protects cells from damage caused by free radicals. They also contain iron and protein, which are essential for healthy immune system function. Furthermore, almonds are a source of zinc, which has been linked to the prevention and treatment of the common cold and flu. [11]
Another benefit of almonds is their positive impact on cardiovascular health. They help protect the heart by maintaining levels of high-density lipoprotein (HDL) cholesterol while reducing levels of low-density lipoprotein (LDL) cholesterol.
10. Green Tea
Green tea is used medicinally for a variety of purposes. It is very high in catechins and polyphenols, which may help prevent cell damage and enhance the body’s immune response. Catechins have powerful antibacterial and antiviral properties, enabling them to combat cold and flu germs. Green tea also contains an amino acid called L-theanine, which helps boost the production of germ-fighting compounds in T-cells. [12]
Other health benefits of green tea include its anti-cancer properties, improved brain function, better weight management, and increased metabolic rate. Several studies have found that green tea catechins can enhance the response of T-cells, which are crucial for attacking viruses. Increased T-cells are associated with an improved immune response. Moreover, research has shown that polyphenols help the body signal when an immune response is needed.
Other Ways to Support Your Immune System
In addition to including healthy foods in the diet, there are some other simple ways that can help to optimize our immune system:
1. Get plenty of good-quality sleep—adults should aim for at least 7 hours of sleep each night, while teenagers need 8-10 hours, and younger children and infants may require up to 14 hours.
2. Engage in regular physical activity—physical activity can reduce inflammation and promote the healthy turnover of immune cells. Jogging, biking, walking, swimming, and hiking are excellent options for maintaining physical fitness.
3. Manage stress levels—lowering stress and anxiety through meditation, yoga, exercise, and other mindfulness practices can help keep the immune system functioning properly.
References:
- Miles EA, Calder PC. Effects of citrus fruit juices and their bioactive components on inflammation and immunity: A narrative review. Front. immunol. 2021Jun24;12.
- Caroline E. Childs, Philip C. Calder, Elizabeth A. Miles. Diet and immune function. Nutrients. 2019Aug16;11(8):1933.
- Hemilä H, Chalker E. Vitamin C for preventing and treating the common cold. Cochrane Database of Systematic Reviews. 2013Jan31;2013(5).
- Zhao C-N, Meng X, Li Y, Li S, Liu Q, Tang G-Y, et al. Fruits for prevention and treatment of cardiovascular diseases. Nutrients. 2017Jun13;9(6):598.
- Prasad S, Tyagi AK. Ginger and its constituents: Role in prevention and treatment of gastrointestinal cancer. Gastroenterol. Res. Pract.. 2015Mar8;2015:1–11.
- Xu C, Mathews AE, Rodrigues C, Eudy BJ, Rowe CA, O’Donoughue A, et al. Aged garlic extract supplementation modifies inflammation and immunity of adults with obesity: A randomized, double-blind, placebo-controlled clinical trial. Clin. Nutr. ESPEN. 2018Jan3;24:148–55.
- Percival SS. Aged garlic extract modifies human immunity. J Nutr. 2016Jan13;146(2).
- Daily JW, Yang M, Park S. Efficacy of turmeric extracts and curcumin for alleviating the symptoms of joint arthritis: A systematic review and meta-analysis of randomized clinical trials. J. Med. Food. 2016Aug1;19(8):717–29.
- Rembold CM. The health benefits of eating salmon. Science. 2004Aug23;305(5683):475–.
- LC.De, Tulipa De. Protective Foods to Develop Immunity of Individuals against COVID 19. Journal Home.2020.2(5) Spl:287-290.
- Capó X, Martorell M, Sureda A, Riera J, Drobnic F, Tur J, et al. Effects of almond- and olive oil-based docosahexaenoic- and vitamin e-enriched beverage dietary supplementation on inflammation associated to exercise and age. Nutrients. 2016;8(10):619.
- Rahayu RP, Prasetyo RA, Purwanto DA, Kresnoadi U, Iskandar RP, Rubianto M. The immunomodulatory effect of green tea (camellia sinensis) leaves extract on immunocompromised wistar rats infected by candida albicans. Vet. World. 2018;11(6):765–70.
