As we reach the peak of the winter flu season, strengthening our immune system has become everyone’s top priority. In addition to staying hydrated and exercising more, why not aim for a balanced diet as part of your daily routine? This time, we invited nutritionist Hu Jiaqi to share the five essential nutrients for boosting immunity, along with two recommended nourishing soup recipes that not only enhance resistance but also provide warmth and nourishment to help you easily combat the flu season!
Seasonal influenza
Seasonal influenza is a common respiratory infection caused by human seasonal influenza viruses. In Hong Kong, seasonal influenza typically occurs from January to March/April and in July and August. There are three types of seasonal influenza that can infect humans: Type A, Type B, and Type C. The main transmission routes include the influenza virus spreading through coughing, sneezing, or droplets from infected patients, and it can also be transmitted through direct contact with the patient’s secretions.
5 Tips to Boost Immunity
1. Balanced Diet: A balanced and nutrient-rich diet consisting of fruits, vegetables, whole grains, high-quality proteins, and healthy unsaturated fats is beneficial for overall health and helps maintain normal bodily functions. Additionally, certain vitamins and minerals can also help improve and strengthen the immune system.
2. Adequate hydration: Drinking enough water helps to eliminate waste from the body and keep the immune system functioning properly. It is recommended to aim for at least 8-10 cups of water daily to meet the body’s fluid needs and to avoid excessive drinking of sugary or caffeinated beverages that may lead to dehydration.
3. Adequate Sleep: Sleep is a crucial time for the body’s repair. During sleep, the body releases proteins known as cytokines, which are part of the immune system. These cytokines can help strengthen the immune system when their production is promoted. Therefore, insufficient sleep weakens the immune system, making us more susceptible to illness. It is recommended that adults get 7-8 hours of quality sleep each night.
4. Regular Exercise: Moderate exercise can improve blood circulation and enhance the function of immune cells, such as walking, swimming, running, and more.
5. Stress reduction: High levels of cortisol (the stress hormone) can sometimes suppress the effectiveness of our immune system. Meditation, yoga, reading, and exercise can help lower stress levels.
5 Essential Nutrients to Boost Your Immune System
| 營養素 | 功效 | 建議每日攝取量 | 主要食物來源 |
| 維他命C | 有抗氧化劑的作用，透過支持各種細胞功能對抗病原體，有助於免疫健康。而且可以刺激白血球的產生和功能，從而保護身體免受感染。 | 根據美國國家學院醫學院 (NAM) 的參考膳食攝取量，建議成年女士每日量最少為 75毫克男士為 90毫克，而每日的上限為 2000毫克。 | 柑橘類水果、奇異果、蕃茄、士多啤梨、三色椒、西蘭花等。但需要注意的是，水果和蔬菜在加熱或長時間儲存時會失去維他命C。 |
| 維他命E | 與維他命C 一樣，同樣都是一種強大的抗氧化劑。它可以保護細胞膜免受自由基損傷，並幫助身體抵抗感染，維持健康的免疫系統。 | 根據美國國家衛生院 (NIH) 的成年人每日建議攝取量為 15毫克。 | 存在於植物油 (花生油、橄欖油)、堅果 (花生、杏仁)、種子 (葵花籽、亞麻籽)、水果 (奇異果、芒果) 和蔬菜 (蕃茄、菠菜) 中。 |
| 鈣 | 透過調節引發抗病毒反應的免疫細胞的活性來增強免疫力並幫助抵抗感染。 | 根據美國國家衛生院 (NIH)，19-50 歲的女士和 19-70 歲的男士為1000毫克，而 51-70 歲的女士和 71 歲或以上的人士為 1200毫克。 | 奶製品是鈣含量非常高的最佳天然來源之一，例如：牛奶、乳酪、芝士。 亦可以選擇硬豆腐、豆製品、乾豆類、杏仁、芝麻、深綠色的蔬菜 (羽衣甘藍、芥蘭、秋葵)、連骨或殼食用的魚類和海產等。 |
| 鋅 | 具有抗發炎和抗氧化特性。它參與某些免疫細胞的產生和負責使所有免疫細胞正常發揮，被稱為免疫系統的「看門人」。鋅缺乏會干擾免疫細胞數量和活動，從而導致增加感染風險並導致發炎性疾病。 | 根據食物安全中心指引，成年女士為 4.9-35毫克，而成年男士為 7-45毫克。 | 通常更容易從動物性來源中吸收，例如牛肉、家禽以及生蠔等海鮮。植物性來源包括鷹嘴豆、豆腐和堅果。 |
| 鐵 | 有助於將氧氣輸送到細胞，並且是對免疫細胞功能很重要的酵素的成分。鐵不足會影響充分免疫反應的能力。 | 根據中國居民膳食營養素參考攝入量，18至49歲的女士為 20毫克，50歲或以上的女士(更年期後)和成年男士為 12毫克。 | 動物性來源：紅肉 (牛肉、豬肉)、內臟 (豬肝、豬紅)、深海魚 (三文魚、吞拿魚)、海鮮 (蜆、蝦)、雞肉等，而動物性來源最容易被人體吸收。 植物性來源：深綠葉蔬菜 (菠菜、羽衣甘藍)、豆類、堅果和種子，其吸收率會較低。 |
Immune-Boosting Soup Recipes Recommendations
| 食譜 | 食材 | 做法 | 營養價值 |
| 蕃茄薯仔牛肉湯 | 蕃茄 2個、薯仔 1個、瘦牛肉片 100克、雞湯 250毫升、薑 2片、蔥 1棵 | 1. 薑切片、蔥切段、蕃茄一開四，薯仔切塊 2. 把牛肉用醃料醃約 15 分鐘 3. 放入牛肉片略，盛起備用 4. 熱鑊爆香薑和蔥，加入蕃茄炒至軟身 5. 加入雞湯後煲滾，放入薯仔煮約15分鐘 6. 最後放回牛肉片略煮 | 蕃茄含有維他命C、薯仔含有鋅，牛肉則含有鋅和鐵，這些都有助維持健康的免疫系統。 |
| 粟米豆腐紫菜湯 | 硬豆腐 1盒、雞蛋 1隻、紫菜 1/4底、粟米 半碗、素上湯 150毫升、水 100-200 毫升 | 1. 把豆腐切塊 2. 把紫菜用水浸軟，瀝乾水份備用 3. 倒上湯及水在鍋中，煮滾後，加紫菜、豆腐及粟米粒 4. 最後慢慢倒入雞蛋成蛋花 | 硬豆腐含有維他命D，而當中加入了雞蛋，蛋黃含有維他命D，有助於幫助吸收鈣質，從而大大提升增強免疫力的功效。 另外，紫菜富含維他命 C、E和鋅，因此在增強免疫系統方面發揮重要作用。這些營養素有助於身體抵抗感染和疾病。 |
Learn more: Hu Jiaqi Kayla – Accredited Dietitian (Hong Kong Dietitians Association)
Dietitian at the “Home Nutrition Center“, Bachelor of Science in Food and Nutrition from Northumbria University, UK. Specializes in designing simple and diverse meal plans tailored to individual lifestyles.
