What do healthy people eat?
While it remains a hotly-debated research area, (respectable) scientists broadly agree that these dietary patterns contribute towards an overall healthy lifestyle:
- Don't consume tobacco products
- Do consume fibrous, nutrient-dense foods (e.g. leafy greens)
- Don't consume trans fats
- Do consume unsaturated fats
- Reduce consumption of added sugars
- If you consume alcohol, do so in moderation
Some scientists argue in favor lowering our consumption of meat and animal products (particularly processed meats), refined carbohydrates (especially sugar but also from processed grains), certain kinds of saturated fats, and excessive amounts of protein. Unfortunately, double-blind randomized placebo controlled studies in humans are often prohibitively expensive and unethical, so it's difficult to reach a consensus on this question. In general, if you can stick to the 6 items above while staying physically active and maintaining good mental health, you're probably on the right track.
Everyone is different, so talk to your doctor or a registered dietitian about what an ideal diet for you looks like.