Antioxidants are powerful compounds found in a variety of foods. Some are essential nutrients whereas others are not.
Antioxidants play a significant role in health and disease. Learn about essential antioxidants, their functions in the body, and how incorporate them into a vegan diet.
Get the Veg Out newsletter for vegan recipes + nutrition content!
What are Antioxidants?
Various types of antioxidants exist in different foods. The two most common antioxidants are essential nutrients – vitamin C and vitamin E 1.
Vitamin C, the primary water-soluble antioxidant, is present in most fruits and vegetables 1. Beta-carotene is another common water-soluble antioxidant, however it is not technically an essential nutrient 1. Water soluble antioxidants work in the watery areas of the body.
Vitamin E, the major fat-soluble antioxidant, is found in fatty foods such as avocados, nuts, seeds, vegetable oils, and, to a lesser extent, leafy green vegetables 1. Fat-soluble antioxidants work in the fatty areas of the body including subcutaneous fat, cell membranes, the brain, and other tissues that contain fat.
Types of Antioxidants
Many antioxidants are not essential nutrients including: 2
These are general categories of antioxidant compounds with many more specific compounds in each category. For example, curcuminoids found in turmeric are a type of polyphenol.
What Antioxidants Do in the Body
There are compounds in the body called free radicals, which can cause damage if levels become too high 1. The body has mechanisms to maintain a good balance of free radicals, but stresses on the body can result in increased levels 1.
The body fights free radicals by using antioxidants that it produces, and those that come from food 1. Antioxidants work by neutralizing free radicals, so the free radicals can no longer cause damage to cells or DNA 1.
Damaging free radicals exist in both watery and fatty parts of the body. Therefore, we need antioxidants to work in both these areas.
Daily Intake Recommendations for Antioxidants
Apart from the few antioxidants that are essential nutrients, there are no set intake levels for antioxidants 3.
Recommended intakes for vitamin C, in adults over age 19, are: 3
- 90 mg per day for men
- 75 mg per day for women
The upper limit of vitamin C for adults is 2000 mg per day 3. This means that consistently consuming vitamin C up to, or over, this amount could result in harm.
Always speak to your doctor before starting any supplements. More is not always better and getting nutrients from food first, if possible, is often a good approach.
Recommended intakes for vitamin E, in men and women over age 19, are: 3
- 15 mg per day
The upper limit for vitamin E in adults is 1000 mg per day 3. This upper limit is specifically for intake from supplements and fortified foods combined (not from vitamin E naturally occurring in foods).
Again, consult a doctor before taking supplements, as they can pose various risks.
How to Consume Enough Antioxidants as a Vegan
Plant-based foods generally contain higher levels of antioxidants compared to animal-based foods 4. Generally, foods with vibrant colors or stronger pigments often have higher antioxidant concentrations.
For example, red onions contain more antioxidants compared to white onions. Leafy greens that are darker in color, like spinach, have more antioxidants compared to a lighter leafy green such as iceberg lettuce.
So, one way to increase antioxidant intake is to focus on selecting foods that are brighter in color or more pigmented.
Additionally, some beverages and “other” foods contain high levels of antioxidants 4. Coffee, espresso, tea leaves, tea leaf powders, and dark chocolate, are rich in antioxidants 4. Tomato-based sauce, basil pesto, sundried tomatoes, and mustard paste, are a few other foods with high antioxidant capacity 4.
Including a variety of foods in your diet can enhance your total antioxidant intake. Foods lower in antioxidants can still be a nutritious and valuable part of your diet as well.
Vegan Food Sources of Antioxidants
While this is fantastic, it’s also important to remember herbs and spices are used in small amounts. So, even though there may be high levels of antioxidant compounds, the total amount you get could still be low.
Regardless, herbs and spices are a great addition to a vegan diet!
The antioxidant content of different foods, even within the same food group, is highly variable 4.
One study quantified the amount of antioxidants in over 3000 food samples from around the world. They grouped foods into categories and reported the average antioxidant concentration of these food groups 4.
Animal-based foods consistently had the lowest antioxidant concentrations, with eggs being the lowest; followed by fish and seafood, dairy products, poultry and meat all coming in at the bottom of the list 4.
Limitations with Reporting Average Antioxidant Concentrations
Average antioxidant concentrations for food groups can easily be skewed by one or two items with very high or low antioxidant amounts.
For example, chocolates and sweets is one category of foods high on the list for having the most antioxidants 4. However, it’s the high percentage dark chocolates (70-99% cocoa) that made it one of the top categories 4.
Also, some of the highest antioxidant food items were dried 4. Without water to dilute the antioxidants, it makes sense that dried foods (ex. dried herbs and spices, dried fruit) would be more concentrated in antioxidants.
This doesn’t necessarily mean these foods are superior to their non-dried counterparts. A fresh apple is a great choice; even though dried apples are more concentrated in antioxidants, it’s just due to the lack of water content.
Antioxidant supplements are everywhere. For the health-conscious vegan, it may be tempting to increase antioxidant intake by supplementing. However, antioxidant supplements are unhelpful at best, and harmful at worst 1, 5, 6, 7, 8.
Always speak to a doctor before starting any supplements.
It’s typically helpful to get nutrition through food first, whenever possible. There are many reasons for this including:
- Supplements contain only a few select antioxidants compared to whole foods which contain a wide range of antioxidants along with other nutrients.
- Supplements are highly concentrated, and more is not always better. Especially with certain medical conditions, highly concentrated supplements could be dangerous.
Whenever possible, try meeting nutrient needs through food first. If you’re concerned about not meeting nutrient needs through food, speak with a dietitian.
Summary: Antioxidants for Vegans
Antioxidants protect cells from damaging free radicals, which is beneficial for overall health. They are abundant in foods, with plant-based foods typically offering higher concentrations.
A diverse diet, with colorful and pigmented foods, is key to ensuring adequate antioxidant intake. Supplements should be approached with caution and under the guidance of a medical practitioner.
Always speak with a doctor before changing your diet or taking new supplements. Please read our full website disclaimer.
About Nicole Stevens
Nicole is a vegan Registered Dietitian (RD) and founder of Lettuce Veg Out.
She helps people thrive on a vegan diet with balanced recipes and easy-to-understand nutrition science.