In your humble opinion, what should the human food plan/diet probably consist of for optimal health?

No processed foods, no sugary drinks. The diet consists of mostly vegetables, fruits and whole grains. No meat, no dairy. Obviously, this is our diet and many disagree with it. But that’s what I believe is the healthiest diet.

It’s different for everyone. Nutrition isn’t an exist science, and humans don’t have interchangable nutritional needs.

I think Michael Pollan got it pretty close: mostly plants, not too much.

The healthiest diet would be fruits and vegetables that you grow yourself; natural sweetners from fruits that you harvest. Water from a spring (if you can find one).

zero high fructose corn syrup. and a good amount of water and fruit.

Mostly plants, with an emphasis on getting enough fiber (usually from whole grains, beans and leafy greens and nuts) people with gluten intolerances and people with celiac disease are really the only ones who need to avoid wheat and other gluten-laden grains.

Low fat, but not non fat. People need to have some fats in their diet to make their bodies function properly. So some low fat dairy products (from sources where the cows are not given hormones) unless the person is lactose intolerant or allergic to milk products. Low or non fat plain yogurt with live bacteria is another good source, and you need some of the “good” vegetable oils such as olive oil and canola oil. Nuts are an excellent source of the “good fats” but because they are full fat, you need to limit your intake of nuts to a small handfull per day.

And you definitely need protein, but not as much as most Americans get with their typical diets. Here’s some info about protein intake. Great vegetarian sources of protein are combinations of whole grains/beans together, tofu and nuts. Quinoa is one of the few plant products that provides a complete protein (meaning that you don’t have to eat it in combination with other foods to get the whole protein). Egg whites are another good source of protein (unfortunately the yolks contain a lot of cholesterol and should probably be limited)

You should eat plenty of foods that are described as being nutrient dense (which rules out all junk food and most processed foods) Good sources are: berries, mushrooms of all kinds (maitake is a powerhouse), leafy greens (kale is a powerhouse), any of the cruciferous veggies like Brussels sprouts, cabbage, broccoli and cauliflower, low or fat free plain yogurt (make sure to get yogurt with live bacteria) sweet potatoes, nuts, peppers (especially red bell peppers), squash, root vegetables and tea. Red and purple fruits and veggies are temendously nutrient dense too (apples, tomatoes, beets). Your best bet is to eat fruits and veggies from the whole spectrum of colors, so that you get the entire complement of nutrients. Don’t just limit yourself to one or two veggies. Try them all!

Most people get their omega 3 fatty acids from fish, but vegetarians can get it from nuts and seeds. The best vegetarian source for omega 3 fatty acids is from ground flax seeds.You can read some info about this topic here

The way food is prepared can effect the way that the nutrients are absorbed by the body. There are people that think a raw food diet is the way to go, but some foods need to be heated to release the nutrients from the vegetable. You can read more about that here

Women, especially during their child bearing years, need to get iron. Luckily there are many good vegetarian sources of iron. You can read about how much iron men, women and children need and where to find it in your food here

If a person decides to be a strict vegan (rather than a vegetarian who probably eats eggs and milk) they will need to find vegan sources of vitamin B-12, which is readily found in animal products, including eggs and milk. You can read about vegan sources for Vit B-12 here

Balanced diet in moderation.

Paleo, at least mostly. It is, after all, what we evolved for.

Imagine if there were no stores. What would you find to eat around where you live? That’s what you should eat. You would be eating plants if you need to, and meat or fish if you caught it.

roots and fruits. raw foods. juicing. live food.
Rasputin who was reputed to have lived for hundreds of years was also reputed to have attended grand state dinners and not eat what was being served but instead little bits from a sack of seeds he carried with him.
Jack LaLane was a vegetarian as was his mentor Bragg (Braggs Amino Acids, yes that Bragg).
I still like my pizza but I know what’s good for me.

Rasputin lived 47 years http://en.wikipedia.org/wiki/Grigori_Rasputin

I try to eat naturally, in other words anything that is as it grows. So I eat fruits and veg, I eat free range meat. I try to avoid what humans have altered in processing. And I do agree with @Simone_De_Beauvoir regarding sugar but I think it should be avoided in any way shape or form.

But on occasion I eat whatever my heart desires which is usually ice cream or rice, pasta, etc. I am 66 and still going strong so it must be working moderately well.

There is no perfect plan. Every human is different. Every activity or inactivity is different.

More and more evidence points to fitness being more important than fatness.

Take 10,000 steps every day and forget about simplistic rules like no carbs, no sugar.

In general make sure to eat a variety of food with all the essential proteins, fat, vitamins and minerals.

Almost all diets are scam. Multibillion dollar scams.

On an average 10,000 steps burn 300–400 calories depending on your weight, height and how quickly you take the steps. One average sized baked potato with butter is over 350 calories. So the 10,000 steps may help you stay healthy, but if you really want to lose weight, you have to watch what you eat and seriously cutting back on white carbs and eliminating sugars will be a great start. Eat mostly lean meats, eggs or beans for protein and lots of veg. When your weight is where you want it to be then slowly add back in healthy carbs. When your weight stabilizes you know you are on your perfect diet plan.

It is difficult to be obese and fit at the same time.