What is oxidative stress?

Oxidative stress refers to the damage to cells that occurs due to the harmful effects of free radicals. Free radicals are unstable molecules that can cause significant damage to cellular components, including DNA, proteins, and lipids. When there is an imbalance between the production of free radicals and the body's ability to detoxify them or repair the resulting damage, oxidative stress results. This condition can lead to various diseases, including cancer, cardiovascular diseases, and neurodegenerative disorders.

In contrast to this, the other options do not accurately describe oxidative stress. While a normal byproduct of cellular respiration does involve the production of reactive oxygen species, it is not synonymous with oxidative stress, which specifically involves damage caused by those species. Excessive ATP production and fermentation relate to energy production processes in cells rather than to the concept of oxidative stress. Thus, defining oxidative stress as damage to cells caused by free radicals captures the essence of the condition effectively.