Juicing’s Impact on Your Immune System

Article by Brooke Shoupe, RN

Article by Stephanie Wells, RD

Juicing can provide an excellent and convenient way to consume an abundance of nutrients that benefit health, in turn, benefit the immune system. 

The immune system is the body’s natural defense against potentially harmful invaders like germs, pathogens, and bacteria. A healthy immune system is vital for overall health and well-being and protects us against infection and disease. 

Fruit juice consumption can affect immunity because nutrition is undoubtedly linked to immune health. Juices may contain various combinations of fruits, vegetables, and herbs.

All these things have a range of vitamins, minerals, and compounds that contribute to health outcomes, including immune function. 

According to The Nutrition Source at Harvard University, the most vital nutrients for immune function are: 

Those that are poorly nourished tend to be more susceptible to viruses and infections. This is why nutrition professionals are so adamant about consuming a nutrient-dense diet. Most of these compounds can be obtained through supplements. However, it’s always better to get these nutrients through food because, for example, a carrot doesn’t just have vitamin A; it also has vitamin C, calcium, biotin, and more.

Nutrients found in fruit and vegetable juices 

Consuming a wide variety of juices is important to ensure you’re getting a range of vitamins and minerals. Many of these compounds overlap in classification because they do so many important things in the body. For example, vitamin C is both a vitamin and an antioxidant. This isn’t an exhaustive list, but the most common nutrients are found in fruit and vegetable juices. 

Antioxidants 

You have probably heard about antioxidants in different contexts – from skincare to cancer treatments. Antioxidants are incredibly important to the body because they fight oxidation caused by free radicals. Free radicals are volatile and damaging to several bodily processes and, if left unchecked, can create a cancerous environment. 

Antioxidants frequently contained in juices are:

• Vitamin C
• Beta-carotene
• Zinc
• Selenium

Phytonutrients

Phytonutrients are often conflated with antioxidants because they have antioxidant and anti-inflammatory properties. However, antioxidants are present in various foods, whereas phytonutrients must come from plants, hinting at the “phyto” in the name. 

Amongst others, some common phytonutrients found in fruits and vegetables are:

• Carotenoids
• Chlorophyll
• Limonoids

All plant foods will contain different and varying levels of phytonutrients, and they are often associated with color. This is why “eating the rainbow” helps ensure you get all the necessary nutrients. 

The immune-boosting properties of juicing

There is overwhelming evidence that compounds in fruits and vegetables stave off disease for a few reasons, but one is that overall health contributes to a healthy immune system. Since the immune system’s job is to recognize and eliminate pathogens, those with strong immunity are less likely to be susceptible to pathogen invasion and, therefore, infection. 

Research indicates that the role of nutrition in immunity and inflammation may be mediated through the gut microbiome. In addition, chronic intestinal inflammation depresses immunity, so maintaining a healthy and diverse gut is integral to maintaining a strong immune system. 

Herbs like turmeric and ginger have been studied for their anti-inflammatory effects and inflammation, which can be great additions to juice recipes.

This study measured participants’ gut bacterial diversity before a three-day juice-based diet and afterward. Results showed an increase in microbial diversity in the gut. This study exhibited how quickly the gut microbiome can adapt to nutrition interventions, which is good! However, a randomized controlled trial (RCT) comparing the effects of a juice-based diet to a strongly regulated whole-food diet would be interesting since most experts recommend a whole-food-based diet over liquid sources of nutrients.  

Incorporating immune-boosting ingredients into your juice 

Citrus juices have been shown to have a positive effect on immunity. Ones that are particularly good for juicing and for immunity are:

Leafy Greens contain essential vitamins and minerals that aren’t necessarily abundant in other fruits and vegetable juices. Some commonly found leafy greens are:

Root Vegetables 

High water-content foods 

To reap the most health benefits from your produce, buy in season. When in season, the fruit or vegetable is picked at its peak ripeness. This is when the plant has had time to fully develop and therefore translates to when it has the highest amounts of valuable nutrients. 

To avoid over-consuming certain nutrients, try a variety of juicing recipes so that you get all of the compounds needed in smaller doses. Mix and match recipes and get creative! It’s all about diversifying your diet. 

Also, maybe try alternating between juices and smoothies so that you can add a bit more nutrient density to smoothies in the form of fiber, protein, and fat.

The limitations of juicing for immune health

Perhaps the biggest drawback to juicing is that the juicing process omits most of the fiber content from fresh fruit and vegetables. When the juice is extracted, the pulp, rind, and skin of fruits and vegetables are discarded, which are the parts of the plant that carry the most fiber. Fiber is critical for gut health, which, as mentioned above, plays an integral role in immune function.

Fresh-pressed juices aren’t a good source of amino acids, except watermelon juice, which contains citrulline and arginine. Amino acids are the building blocks for protein. Some are essential, and some or non-essential, meaning our body naturally produces some, and others we must obtain from food sources. We consume most of the necessary amino acids from animal products. This is another reason to consume juices alongside a well-rounded diet to receive the maximum benefits! 

A lot of things can strain the immune system, like age, environmental factors, excess weight, poor diet, chronic diseases, stress, and inadequate sleep. Some aspects of life are unavoidable, and others can be managed. 

Juicing can be a part of a well-rounded, healthy diet and also help people manage their weight. These two things cannot make up for poor sleep habits or an aging body, but they can help facilitate a healthy immune system. 

Most nutrients have a set tolerable upper limit (UL). If you haven’t heard of this value, you may have come across the recommended dietary allowance (RDA) instead. This point is set based on data where no adverse health outcomes were observed lower than this amount.

For adults, the UL for vitamin C is 2,000 mg per day, whereas the RDA is 75 mg for females and 90 mg for males. Any amount under 2000 mg is fine, but there are no additional benefits to exceeding the RDA. For example, just one six-ounce glass of orange juice contains around 90 mg, which meets the daily RDA for vitamin C. 

As mentioned above, some people supplement with these nutrients, but this can lead to overconsumption. So, with all of this said, you can actually overdo it on the nutrients. On the other hand, if you are already supplementing with vitamin C, for example, you probably don’t need to drink citrus juice every day since you likely still get additional sources of vitamin C in your diet.

Conclusion 

Responsible juicing can be part of a healthy lifestyle, but whole fruits and vegetables provide greater health benefits to juices. However, fresh juices can be a vehicle to deliver critical nutrients to support immunity to an individual that doesn’t get enough of these compounds through diet alone. For example, juicing is a tasty way for kids and picky eaters to consume enough good stuff from fruits and vegetables. 

Just ensure not to over-consume nutrients by using a wide variety and avoiding supplements while juicing. Include fiber, protein, and healthy fats in your diet since juicing doesn’t cover these nutrients effectively. When bearing these things in mind, juicing is a great way to create an optimal environment for your immune system to flourish.