Just for the sake of argument, since a few comments are talking about getting or staying lean I will quote a couple of experts in this field, Mike Israetel (Renaissance Diet) and Eric Helms (Muscle and Strength Pyramid: Nutrition)
According to Israetel, the most important factors in terms of nutrition for body composition are (from most to least important): calorie balance, macronutrients, nutrient timing, food composition, and supplements. By food composition he is talking specifically about protein bioavailability, glycemic index, and fat type (saturated vs. unsaturated).
Helms: energy balance, macronutrients, micronutrients, nutrient timing, supplements
Helms goes on to say: "Now this is something that is very prevalent throughout the entire fitness community as a whole� Many people advocate it and have done so for years� These believers in the “good food vs� bad food” mindset include some very smart people, people with great physiques, and a lot of people that have had quite a lot of success with their own goals� However, despite the fact that you can achieve success with this approach I don’t see it as a long-term solution and I think that it can lead to developing unhealthy relationships with food� We shouldn’t have to maintain borderline eating disorders just to keep a lean physique� As opposed to trying to avoid the consumption of “bad foods”, I think a better mindset to adopt is approaching nutrition with the goal of being inclusive instead of exclusive�
Remember that you don’t get extra credit for eating only healthy foods� Once you’ve met your basic requirements you don’t get gold stars for consuming additional micronutrients� There’s no food critic in your throat who tells you “this is good, this is bad, this is good, etc�,” there’s just your body getting its nutrient needs, and once it gets more than enough, it doesn’t continue to benefit from more� It’s not a question of whether a bowl of oatmeal is better than a candy bar� Rather than assessing which food is good or bad, you need to assess if your entire diet is good or bad� Believe it or not, a rigid “clean vs� dirty” diet can actually result in a poorer nutrient profile than an approach that includes a broader spectrum of foods� "