The Antioxidant Saga: Why We Need Vitamins C and E

By Perrin Braun, November 5, 2021

antioxidants in fruits and vegetablesThe cells in your body wage war against the elements every single day: infections, viruses, pollution, poor diet, sunlight, and over-exercising can do some serious damage. Not to mention the threat from free radicals, which are the molecular byproducts of turning food into energy, and which have the potential to damage your cells and genetic material. The good news is that we aren’t completely defenseless against these types of onslaughts: antioxidants work to protect cells from damage by free radicals and other substances.

best ways to heal your gutWhen free radicals damage your cells, inflammation can occur. Inflammation is your body’s way of protecting itself from harmful stimuli, including damaged cells, irritants, or pathogens. It plays a critical role in maintaining your body’s immune system and heart function, and in keeping you healthy. But high levels of inflammation can cause problems, for example, weakening the walls of your blood vessels and making them less effective at carrying oxygen to your muscles. To optimize the way that you feel and perform, it is important to keep inflammation low. 

Click here to learn how InsideTracker can provide you with personalized recommendations to boost your antioxidant levels!

Two of the best-known antioxidants are vitamins C and E, which help to slow down or stop the processes that damage the cells in your body. These vitamins also are essential for many other processes in your body. Since cellular damage is often responsible for aging and the development of chronic disease, these two vitamins are being vigorously studied by scientists in order to understand what specific conditions they may benefit the most.


Why are antioxidants important?

Free radicals such as superoxide (O2-), hydrogen peroxide (H2O2), or peroxynitrite (OONO-) can damage cells, proteins, fats, and DNA. In a process called “oxidative stress” free radicals steal electrons from nearby substances, a change that can dramatically alter the cell’s structure or function, potentially changing the instructions in DNA. For instance, according to the Harvard School for Public Health, free radicals can make an LDL cholesterol molecule more likely to get trapped in an artery wall, or they can alter the flow of what enters a cell and what leaves it. Antioxidants work by giving electrons to free radicals; the extra electron stabilizes them, preventing them from causing further damage to the cells in the body. There are hundreds of different types of substances that have antioxidant properties; read on to find out more about antioxidants vitamins C and E.

Vitamin C is a water-soluble vitamin, which is excreted by the body through urine and sweat and therefore needs to be replaced each day. This vitamin is essential for the creation of collagen (a structural support for your skin), protein metabolism, and wound healing. It also plays an important role in your immune system and improves the absorption of non-heme iron, which is the form of iron that is found in plant-based food (vegetarians take note!). However, vitamin C is probably best known for its antioxidant properties, and has even been shown to help regeneration other antioxidants within the body, including vitamin E.

In addition to neutralizing free radicals with its antioxidant properties, vitamin C also plays a role in controlling infections. One study on ultramarathon runners showed that vitamin C supplementation can even enhance resistance to upper-respiratory-tract infections. This vitamin aids in the production of collagen, which is a tissue that is needed for your bones, blood vessels, teeth, and gums. Another study suggested that an increase in vitamin C consumption is associated with reduced inflammation in individuals who have elevated inflammation levels.

food sources of vitamin c

Unlike vitamin C, vitamin E is a fat-soluble compound, which is stored naturally in the body, so you don’t need large doses of it to stay healthy. Naturally occurring vitamin E comes in eight chemical forms, but alpha-tocopherol is the only form that is recognized to meet your body’s needs. A powerful antioxidant, vitamin E interferes with the production of free radicals in the body. Vitamin E also plays a role in the functioning of your immune system and in maintaining healthy blood vessels. Just like vitamin C, you must get vitamin E from foods or supplements, because your body does not make this essential vitamin. Scientists are currently researching whether vitamin E might prevent or delay the chronic diseases that are frequently associated with free radical damage.

While vitamins C and E are important for everyone, athletes may want to pay special attention to these vitamins. For instance, one study showed that endurance athletes have higher levels of inflammation and lower levels of vitamin E. Athletes who have over-training syndrome, which is a result of too much exercise with too little recovery time, have been shown to have higher levels of oxidative stress. The InsideTracker Performance Plan can help you identify over-training syndrome by measuring inflammation, testosterone, and creatine kinase, a marker of muscle damage. In addition, InsideTracker will also suggest simple changes you can make to help recover from over-training syndrome, such as getting more and better quality sleep and adding antioxidant-rich foods to your diet.


How do you know if you’re getting enough vitamins C and E?

You’ll definitely know if you’re not getting enough dietary vitamin C. Sailors who spent long months out at sea without fresh fruit or vegetables often contracted scurvy, a severe form of vitamin C deficiency that could result in death, fatigue, inflammation of the gums, joint pain, and poor wound healing. Symptoms of milder vitamin C deficiency include fatigue, weight loss, joint and muscle aches, bruising, dry hair and skin, and any sudden mood changes. The groups of people who are at a greater risk for vitamin C deficiencies include smokers (smoking affects the absorption of the vitamin from food) and individuals with a medical condition that affects the body’s ability to absorb food, such as Crohn’s disease and ulcerative colitis. While scurvy is extremely rare in developed countries, because of over-supplementation, vitamin C toxicity might present a problem. If you take over 2,000 mg of vitamin C per day, you could experience symptoms such as diarrhea, nausea, and stomach cramps, so be careful how much you consume.

As far as vitamin E goes, deficiency is also rare in developed countries, but because the digestive tract requires fat to absorb the vitamin, people with fat-malabsorption disorders may not get enough vitamin E from their food. Adults should not take more than 1,000 milligrams a day of vitamin E since getting too much can cause nausea, diarrhea, fatigue, and muscle weakness.


vitamin e studies

What are some good sources of vitamins C and E, and how much do you need?

Most fruits and vegetables are good sources of vitamin C. Specifically, citrus fruit (such as oranges and grapefruit), cantaloupe, strawberries, papaya, dark leafy green vegetables, sweet potatoes, and red pepper all contain healthy amounts of vitamin C.  According to the National Institutes of Health, adult men should aim for 90 milligrams of vitamin C each day, while adult women should get about 75 milligrams. A half a cup of raw red peppers contains a whopping 95 mg of vitamin C, and ¾ cup of orange juice clocks in at 92 mg. Also, one medium orange alone contains 70 mg of vitamin C, and ½ cup broccoli contains 51 mg. InsideTracker’s Nutrition Page and Food Basket Page can suggest many other delicious sources of vitamin C.

The alpha-tocopherol form of vitamin E is found in nuts, seeds, leafy green vegetables, fortified cereals, and vegetable oil. It’s not hard to get the RDA of 15 milligrams of vitamin E; for example, one ounce of sunflower seeds contains 7.4 mg of vitamin E in the alpha-tocopherol form, which is about half of what you need for the day. A one-ounce serving of dry roasted almonds provides 6.8 mg vitamin E, 2 tablespoons of peanut butter contain 2.9 mg, and a half-cup of boiled spinach has 1.9 mg.

While the antioxidants that are found naturally in fruits and vegetables may help prevent chronic disease, very high doses of antioxidants have not been shown to offer any specific health benefits.  We know that free radicals contribute to chronic diseases like cancer, heart disease, and Alzheimer’s disease. Although antioxidants won’t automatically fix these problems, eating a diet rich in fruit, vegetables, and whole grains—which are great sources of vitamins C and E—will reduce inflammation, boost your immune system, and improve your overall well-being and athletic performance. So, sign up for InsideTracker today to find out how you can incorporate more antioxidant-rich foods into your diet!


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