The less food required, the likely healthier the person, with the exception of being nutritionally complete. Food is necessary, but it also disturbs homeostasis.

Designing a nutritionally complete diet that includes all the vitamins and minerals using the least amount of different foods as possible is a challenging task.

Here's an example of a nutritionally complete diet using the least amount of different foods possible:

1. Brown rice: Brown rice is a good source of carbohydrates and some micronutrients like magnesium and selenium.

1. Lentils: Lentils are a good source of plant-based protein, fiber, and micronutrients like folate, iron, and magnesium.

1. Spinach: Spinach is a leafy green vegetable that is rich in vitamins and minerals, including vitamin A, C, and K, iron, and calcium.

1. Carrots: Carrots are an excellent source of beta-carotene, which the body can convert into vitamin A. They also contain fiber and some micronutrients like potassium.

1. Salmon: Salmon is a fatty fish that is an excellent source of omega-3 fatty acids, protein, and micronutrients like vitamin D and selenium.

1. Almonds: Almonds are a good source of healthy fats, protein, and micronutrients like vitamin E and magnesium.

1. Eggs: Eggs are a good source of protein, healthy fats, and micronutrients like choline, vitamin D, and selenium.

1. Oranges: Oranges are a good source of vitamin C and fiber.

Here is an example meal plan that provides most of the daily recommended nutrient intakes:

1. Breakfast: Omelet made with 2 eggs, spinach, and 1/4 cup of chopped almonds. One medium-sized orange.
2. Lunch: Brown rice and lentil salad with steamed carrots and spinach. Dressing made with olive oil and lemon juice.
3. Dinner: Grilled salmon with steamed spinach and brown rice. One medium-sized orange for dessert.

This meal plan provides a balanced intake of macronutrients and micronutrients, including all the essential vitamins and minerals, with the least amount of different foods possible.