Chapter 3: Phytochemicals and Immunity
Phytochemicals have been shown to have an important impact on your immune function and overall well-being. However, many people are unaware that they exist. Unlike superfoods, antioxidants and other well-publicized health-promoting foods, phytochemicals have received little attention from the media. Therefore, they are often overlooked, even by those who are eager to give their health a much-needed boost.
In fact, phytochemicals have been researched for decades, but it’s only recently that they’ve been studied in humans. Yet, findings have shown that these naturally-occurring plant chemicals could have a major positive effect on your well-being and immunity. So, it’s definitely worth finding out more about them and how you can add them to you daily diet. This will promote your immune system’s function and help it to keep you protected from harm.
What are Phytochemicals?
Phytochemicals are plant chemicals that occur naturally and, when consumed, have been shown to interact with the immune system on every level and support it effectively. Phytochemicals have even been shown to inhibit cancer at each stage of its development, stopping new cancer cells from forming, inhibiting their growth, and removing the toxins that can cause cancer.
They can even influence the gene activity that is involved in the development of cancer and suppress the hormones that have been shown to stimulate the growth of certain types of cancer. With this in mind, it’s important to be aware of the most beneficial phytochemicals that you could be adding to your daily intake.
The Most Beneficial Phytochemicals
There are several types of phytochemicals that have been shown to be highly beneficial for your immunity. These bioactive chemicals have been proven to slow down and halt cancer progression by inhibiting cell division, altering gene expression, reducing inflammation and free radical damage, and inhibiting the blood supply to tumors.
Quercetin is one frequently studied flavonoid. It can be found in green tea. It blocks the production of hormone receptors, growth factors and the other components known to promote cancer growth. Some other foods that contain phytochemicals that can be beneficial for your immune system include avocados, cranberries and pomegranates.
Cranberries contain a number of phytochemicals including polyphenols, flavanol glycosides, proanthocyanidins, phenolic acids and anthocyanins. These compounds can reduce the load on your immune system, helping to keep you safe from illnesses.
Meanwhile, avocados are a rich source of carotenoids and pomegranates are packed with ellagic acid and hydrolysable ellagitannins, both of which are polyphenols.
Black tea and garlic have also been shown to be beneficial phytochemicals. Garlic contains organoselenium metabolites while black tea contains polyphenols like epigallocatechin-3- gallate.
Eating foods that are a range of colors is one of the best ways to benefit from phytochemicals in your diet. Red foods like tomatoes contain lycopene, green food like broccoli contains glucosinolates, and onion and garlic contain allyl sulfides. All of these compounds are known to boost immunity exponentially, so you should try every day to make sure that you include foods of several colors in your meals to give yourself the best chance of achieving optimal immunity.
Chapter 4: Antioxidants and Immune Health
Antioxidants have recently been shown to have a powerful part to play in improving your immunity and overall well-being. There has been a lot of news in the media over the last few years touting antioxidants as the biggest and best thing to include in your diet to ensure optimal health. But what are they, and how do they work?
What are Antioxidants?
Antioxidants are substances that are known to slow down or even prevent the damage caused to the body’s cells by free radicals – the unstable molecules produced by the body in reaction to environmental factors and other stresses.
Antioxidants can come from either artificial or natural sources. Some plant-based foods are believed to be packed with antioxidants, and plant-based antioxidants are a form of phytonutrient.
Some antioxidants are produced by the body itself. These are known as endogenous antioxidants. Those that are derived from outside your body are called exogenous antioxidants. Antioxidants are known to protect against oxidative stress – the cell damage caused by free radicals in the body.
Some of the processes and activities that can cause oxidative stress include:
· Excessive exercise · Mitochondrial activity · Ischemia and reperfusion damage
· Tissue trauma because of injury or inflammation
· Consuming processed and refined foods, artificial sweeteners, trans fats and certain additives and dyes
· Environmental pollution · Exposure to drugs, pesticides and chemicals
· Industrial solvents
When cell damage occurs, the result can be:
· Excess release of free copper or iron ions
· Activation of phagocytes, one of the white blood cell types that combat infection
· Disruption in the electron transport chains
· Increased enzymes that generate more free radicals
These all cause oxidative stress.
Oxidative stress is linked to vision loss, atherosclerosis, and cancer due to cell changes caused by free radicals. Consuming more antioxidants can reduce these risks.
The Role of Free Radicals
Free radicals are waste substances created by cells when the body reacts to its environment and processes food. When your body can’t remove the free radicals efficiently, the result can be oxidative stress which harms the cells and impairs the function of your body.
Oxidative stress caused by free radicals is linked with a host of diseases including cancer, heart disease, strokes, arthritis, immune deficiency, respiratory diseases, Parkinson’s disease, emphysema, and other ischemic and inflammatory conditions. When you consume enough antioxidants, the free radicals are neutralized, boosting your overall health.
Which Foods Contain Antioxidants?
It’s believed there are hundreds or even thousands of antioxidants. Each one has its own role to play and interacts with others inside the body to keep it functioning properly. Some examples of antioxidants include:
· Vitamin A
· Vitamin C
· Vitamin E
Flavonoids, catechins, flavones, phytoestrogens and polyphenols are all forms of antioxidants found in plant-based food.
All antioxidants serve their own function and cannot be interchanged with others. This is why you need to eat a varied and balanced diet.
Some foods that are known to be rich sources of antioxidants include:
· Vitamin A – liver, eggs, and dairy products
· Vitamin C – vegetables and fruits including bell peppers, oranges, and berries
· Vitamin E – seeds and nuts, vegetable and sunflower oils, and leafy green vegetables
· Beta-carotene – vegetables and fruits in bright colors like peas, mangos, carrots, and spinach
· Lycopene – red and pink vegetables and fruits like watermelon and tomatoes
· Lutein – leafy green vegetables, oranges, papaya, and corn · Selenium – corn, rice, wheat, nuts, whole grains, legumes, cheese, and eggs
Other foods said to be good antioxidant sources include:
· Legumes like kidney beans and black beans
· Black and green teas
· Red grapes
· Dark chocolate
· Goji berries
It’s important to note that cooking certain foods may decrease or increase their level of antioxidants. For example, when tomatoes are cooked the lycopene inside them becomes easier for the body to use and process. Conversely, zucchini, peas and cauliflower all lose some of their antioxidant potency when they’re cooked.