Upper Limit to Benefits From Fruits and Vegetables?

Is there an upper limit to the benefits one gains from consuming fruits and vegetables? Of course eating 5 servings of fruits and vegetables per day is better than 1, and 10 is likely better than 5, but is 12 better than 10? Is 15 better than 12? Assuming adequate macronutrient intake, micronutrient intake, a minimum of 8-10 servings of fruits and vegetables, and the same calories and fiber in both diets, would a diet containing more fruits and vegetables be healthier than another containing less? I suppose this also depends on what the fruits and vegetables are replaced with. I would assume there is a greater reduction in health (if there is one) from replacing fruits and vegetables with highly processed foods compared to replacing them with whole grains or legumes (which may not result in any reduction in health whatsoever). Another way to ask this question might be “Do the health benefits of fruits and vegetables result in a linear dose-response relationship?” If they do not, is the cut-off or where it starts to slow down around 8-10 for most people? (Hence the recommendations to eat 8-10 servings)

I do think there’s a dose dependent relationship between fruit and vegetable intake and most health outcomes. Like most dose-dependent relationships in humans however, it’s not linear.

The recommendation to eat 8-10 servings per day is mostly geared towards something that is possible for a large swath of the population, though other countries aren’t as optimistic and recommend “5 a day”.