RecipesFrom the test kitchen

Lentil and Spinach Soup

A one-pot, iron-focused lunch soup that finishes with fresh spinach and a squeeze of lemon so the vitamin C lands right next to the plant iron.

Lunchiron rich
45Total mins
10Prep
35Cook
4Servings
Recipe density
Plate study · drawn from this recipe's foods

Method

  1. 1

    Warm the olive oil in a large pot or Dutch oven over medium heat. Add the onion and carrots with a pinch of salt and cook for 5 to 6 minutes, stirring now and then, until the onion turns translucent and the carrots start to soften.

  2. 2

    Stir in the garlic and cumin and cook for 1 minute, just until fragrant. If you are using whole cumin seed, let it sizzle in the oil so it toasts.

  3. 3

    Add the rinsed lentils and the water or broth. Bring to a boil, then drop the heat to a gentle simmer. Cook uncovered for 25 to 30 minutes, until the lentils are tender but still hold their shape.

  4. 4

    Taste and season with salt and black pepper. If the soup looks thicker than you like, thin it with a splash of hot water.

  5. 5

    Turn off the heat, add the spinach in two big handfuls, and stir. It will look like too much, then wilt down into the soup within a minute.

  6. 6

    Stir in the lemon juice off the heat so its vitamin C is not cooked away. Taste one more time and adjust salt.

  7. 7

    Ladle into four bowls and serve hot, with an extra lemon wedge on the side if you like it sharper.

Why this scores well

Original analysis by NutriVerdict

The two headline ingredients here are also two of the strongest performers in our index. Raw spinach scores a perfect 100 on our Nutrient Density Score, packing 2.71 mg of iron, 2.2 g of fiber, and 558 mg of potassium into every 100 g for only 23 calories. Raw lentils score 70 and carry the heavy load: 6.51 mg of iron, 10.7 g of fiber, and 677 mg of potassium per 100 g, which is why one cup of dry lentils supplies most of this pot's minerals. Lemon juice (90) contributes 38.7 mg of vitamin C per 100 g, the absorption helper for all that plant iron. Cumin seed (95) is quietly one of the most iron-dense items in the entire database at 66.4 mg per 100 g, so even a teaspoon adds a measurable bump. Carrots (94), garlic (80), and onions (67) round out the base. Add it up and each bowl delivers about 4.5 mg of iron, 7 g of fiber, and roughly 690 mg of potassium.

Tips

  • Add the lemon juice off the heat, always. Vitamin C is heat-sensitive, and it is the piece of this recipe that helps your body pull more iron out of the lentils and spinach.
  • Skip coffee or tea with this meal if iron is your goal. The polyphenols in both can get in the way of non-heme iron absorption, so save them for an hour or two later.
  • The soup thickens a lot in the fridge as the lentils keep drinking the broth. Reheat with a splash of water and a fresh squeeze of lemon and it comes right back.

Note: This is food, not medical advice. The iron in lentils and spinach is non-heme iron, which your body absorbs less readily than the iron in meat, and that is exactly why the lemon finish matters: vitamin C eaten in the same meal improves non-heme iron uptake. All nutrient figures come from the USDA FoodData Central records behind our index.