Iceberg Lettuce
Iceberg lettuce doesn’t offer many nutrients. It has very few calories (a cup of iceberg lettuce has only 8 calories, which is low compared to arugula with 28 and kale with 33), and it has a neutral effect on the digestive tract. However, most of the iceberg lettuce is made up of water.

Arugula
Arugula is rich in vitamin A and has beneficial effects on brain and joint function. It’s also rich in iron and is especially recommended for athletes and before heavy exertion, as iron helps blood cells carry more oxygen to the muscles. The best way to eat arugula is with high-quality olive oil and sprinkled with parmesan.
Romaine Lettuce
Commonly referred to as romaine lettuce, it was a very popular dish among the Romans, especially during their large feasts. It has a lot of vitamins K, C, and A, boosts the immune system, and is best with olive oil, green onions, green peppers, and you can also add feta cheese.

Spinach
Spinach is a rich source of iron, manganese, and plenty of antioxidants. It is a must-have food for pregnant women and children, and it’s also recommended for the elderly. It’s good to eat it in all forms – as a salad and also as a sauce.
Kale
Kale, including Brussels sprouts, is the champion of nutrients among salads. It has a lot of calcium, potassium, iron, manganese, and is high in vitamins A and C... It’s best served with natural yogurt and as few additives as possible.