Will Boosting Antioxidants Benefit COPD Patients?

Foods containing vitamins A, C and E may give you the biggest boost

Blueberries are a source of antioxidants.
Blueberries are a source of antioxidants. Multi-bits/Getty Images

If you have COPD, you might want to consider boosting your intake of foods containing certain antioxidant vitamins, including vitamins A, C and E — there's some evidence that doing so may well benefit your health.

In fact, recent medical research indicates that antioxidants eventually could represent a promising therapy for COPD. However, you shouldn't run out just yet to stock up on over-the-counter supplements, since clinicians haven't figured out exactly what works and what doesn't in COPD.

In fact, taking some supplements may be counterproductive.

Instead, the best advice is for you to focus on making your diet as healthy as possible, which means eating lots of fruits and vegetables. Here's what we know so far, plus what we don't know, about antioxidants and COPD.

What Exactly Are Antioxidants?

Antioxidants are naturally occurring or synthetic substances that help protect cells from the damaging effects of free radicals, which are highly reactive compounds created during normal cell metabolism. Free radicals can damage cells — even normal, healthy cells — and antioxidants can prevent that damage.

You might be familiar with vitamin C, which may be the most extensively studied antioxidant. But there are many more antioxidants. You can get antioxidants from fruits and vegetables, and your body actually manufactures some of its own antioxidants.

What Are Oxidants and Oxidative Stress?

Put simply, oxidation is an interaction between oxygen molecules and other substances, and an oxidant is a substance capable of causing that interaction.

When you peel an apple and it starts to turn brown, that's oxidation — enzymes in the fruit are the oxidants in this case, and the oxygen in the air causes the reaction.

Oxidation also occurs in living tissue, including in your lungs. The lungs are continuously exposed to oxidants, generated from either inside the body (free radicals released from your cells), or outside the body (e.g.

cigarette smoke or air pollution).

Oxidative stress occurs when the balance between oxidants and antioxidants shifts in the direction of oxidants, caused by either an excess of oxidants or a deficiency of antioxidants.

How Does Oxidative Stress Relate to COPD?

Cigarette smoke, the primary cause of COPD, increases the level of oxidants in the lungs, resulting in a decrease of antioxidants. This promotes oxidative stress and the destruction of alveoli, the tiny air sacs in the lungs where oxygen and carbon dioxide are exchanged.

Oxidative stress has also been linked to inflammation of the airways of the lungs, something that's common in COPD patients.

What Does the Research Say?

The use of antioxidants to prevent and treat disease is still controversial, although some research shows a potential benefit. The following are examples of what some of the research is saying about antioxidants and lung health:

  • Low levels of the antioxidant vitamin C, among other contributing factors, have been found to possibly increase the amount of oxidative stress within the body. However, other investigators have found that vitamin C may be linked to an increase in oxidative stress and therefore, not recommended.
  • Higher levels of antioxidant vitamins A, C, E and beta-cryptoxanthin (a substance converted to vitamin A in the body), along with selenium and several other elements, were independently associated with better lung function and higher levels of FEV1, a commonly used lung function test. It's not clear, however, whether this was just a coincidence.
  • An increase of 40 milligrams in vitamin C intake per day led to a small but significant increase in lung function in one study.
  • When comparing standard treatment of COPD (inhaled bronchodilators and corticosteroids), to standard treatment plus eight weeks' worth of vitamin E supplementation, no additional clinical benefit was found in COPD patients, although extra vitamin E did help patients produce more of their own endogenous antioxidants.

Antioxidant-Rich Food Sources

Consuming foods from a wide variety of sources is part of a healthy, well-balanced diet. If you want to include plenty of antioxidant-rich food sources in your diet (which is always a good idea), the U.S. Department of Agriculture has provided a ranking of the top 20 food sources of antioxidants to include on your shopping list:

  1. Small red beans, dry, 1/2 cup
  2. Wild blueberries, 1 cup
  3. Red kidney beans, 1/2 cup
  4. Pinto beans, dry, 1/2 cup
  5. Cultured blueberries, 1 cup
  6. Cranberries, 1 cup
  7. Artichoke hearts, 1 cup
  8. Blackberries, 1 cup
  9. Prunes, 1/2 cup
  10. Raspberries, 1 cup
  11. Strawberries, 1 cup
  12. Red delicious apples, 1
  13. Granny Smith apples, 1
  14. Pecans, 1 ounce
  15. Sweet cherries, 1 cup
  16. Black plums, 1
  17. Russet potatoes, cooked, 1
  18. Black beans, dried, 1/2 cup
  19. Plums, 1
  20. Gala apples, 1

While the list above contains some excellent sources for antioxidant-rich foods, the following foods, also loaded with powerful antioxidants, might make good additions to your diet:

  • Green tea
  • Cruciferous vegetables
  • Fish
  • Tomato products
  • Flax
  • Olive oil
  • Kelp/seaweed
  • Collard greens, spinach and kale
  • Broccoli sprouts
  • Pomegranates
  • Pineapple
  • Avocado
  • Carrots
  • Exotic Mushrooms
  • Dark chocolate and hot cocoa
  • Turmeric
  • Garlic
  • Ginger

The Bottom Line

In light of the controversy surrounding antioxidants and COPD, further evidence is needed to support claims that they are beneficial for lung health. Until then, be sure to talk with your primary care provider or nutritionist regarding a diet plan to suit your individual needs.

To learn more about what to eat for a COPD diet, visit the following links:

Nutritional Guidelines for a COPD Diet

Healthy Eating Tips for the COPD Patient

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Can U et al. Role of oxidative stress and serum lipid levels in stable chronic obstructive pulmonary disease. Journal of the Chinese Medical Association. 2015 Dec;78(12):702-8.

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Fischer BM et al. COPD: balancing oxidants and antioxidants. International Journal of Chronic Obstructive Pulmonary Disease. 015 Feb 2;10:261-76.

Hu G, Cassano PA. Antioxidant nutrients and pulmonary function: the Third National Health and Nutrition Examination Survey (NHANES III). Am J Epidemiol. 2000 May 15;151(10):975-81.

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McKeever TM, Lewis SA, Smit HA, Burney P, Cassano PA, Britton J. A multivariate analysis of serum nutrient levels and lung function. Respir Res. 2008 Sep 29;9:67.

Pirabbasi E et al. What are the antioxidant status predictors' factors among male chronic obstructive pulmonary disease (COPD) patients? Global Journal of Health Science. 2012 Nov 4;5(1):70-8.

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Siedlinski M, Postma DS, van Diemen CC, Blokstra A, Smit HA, Boezen HM. Lung function loss, smoking, vitamin C intake, and polymorphisms of the glutamate-cysteine ligase genes. Am J Respir Crit Care Med. 2008 Jul 1;178(1):13-9. Epub 2008 Apr 17.

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