Optimizing Nutrient Absorption, One Bite at a Time

by Theresa DeLorenzo

Last month I talked about eating your nutrients instead of taking them via pill form to optimize absorption. Well, there is more to the story. Many nutrients are absorbed better when our body needs more of them. Some nutrients inhibit the absorption of others. Others enhance the absorption of nutrients. And contaminants in our food can impact how we absorb and use the nutrients we take in.Let’s start with calcium. Our bones are made of calcium. We use calcium for muscular contraction and nerve transmission. Without enough calcium, we are at risk for fractures, muscle aches, cramps and spasms, difficulty swallowing, and abnormal heart rhythms.

We get calcium from dairy products, fortified milk alternatives, almonds, cooked green and leafy vegetables, beans, and tofu. Green and leafy vegetables contain fibrous substances called oxalates and phytates. These substances are bound to the calcium in the vegetables rendering them unabsorbable. But cooking the vegetables, whether sautéing, microwaving, roasting or baking, breaks the bond between the calcium and fibrous substances, allowing for calcium absorption. You can also enhance the absorption of calcium from green leafy vegetables and other calcium-rich foods by adding a source of vitamin C to the food. Examples of vitamin C-rich foods include berries, lemon, tomatoes, peppers, and jalapenos.

Green leafy vegetables also contain iron. Like calcium, iron is bound to oxalates and phytates. Cooking releases the iron for absorption. Vitamin C also enhances the absorption of iron from these sources.

Other iron-rich foods include beans, raisins, meat, poultry, fish, and fortified grains. We use iron to make hemoglobin, which then transfers oxygen to our lungs and muscles.

Using a cast iron pan can enhance the intake of iron. However, metals, such as mercury found in fish and aluminum found in cookware, bind to the same absorption sites as iron and unfortunately are absorbed preferentially, potentially leading to iron deficiency if consumed frequently. Fish containing high amounts of mercury should be avoided. This includes swordfish, tilefish, and shark. Tuna contains some mercury and should be limited to four ounces per week. Symptoms of iron deficiency include fatigue, difficulty breathing, headache, dizziness, cold hands and feet, and weakness.

Then there are the fat-soluble vitamins, vitamins A, D, E, and K. Vitamin A is obtained from orange vegetables such as carrots, squash, and sweet potatoes and is used in the body for vision and skin health and in the immune and reproductive systems. Vitamin D is found in dairy products, shiitake mushrooms, and fatty fish. Our body uses vitamin D to regulate and balance calcium absorption in our blood, immune function, and inflammation control. Vitamin E is found in avocados, nuts, seeds, and sunflower, safflower, and sesame oil. Vitamin E is an antioxidant that helps stabilize free radicals in our body, protecting us from cancer and cardiovascular disease. Finally, you can find vitamin K in green leafy vegetables such as broccoli, asparagus, and brussel sprouts. Unlike calcium and iron, vitamin K can be absorbed from the raw versions of foods.

Because all of these vitamins are fat-soluble, some fat must be present when consumed to optimize absorption. So add olive oil to broccoli (and lemon so that the calcium and iron can be absorbed), parmesan cheese to spinach, use low-fat milk instead of skim milk, or add hemp seeds on top of sweet potato to aid in absorption.

Check out some of my favorite nutrient-enhancing combinations!

Fried Egg Sandwich with Spinach and Tomato

  • 2 eggs
  • 1 cup spinach
  • 2 slices tomato
  • 2 slices whole-grain bread
  • 1 tbsp. Smart Balance butter
  • 1 tbsp. olive oil

Heat ½ tbsp. olive oil in a pan and the other ½ tbsp. olive oil in another pan. Fry the eggs in one of the pans and sauté the spinach in the other. Meanwhile, toast the whole-grain bread. When the toast is ready, spread the butter on the toast and top with spinach, tomato, and egg. You can serve open-faced or as a sandwich.

The cooked spinach provides iron and calcium. The vitamin C-rich tomato enhances the absorption of both.

Tofu Salad Sandwich- DO NOT knock this one until you’ve tried it!

  • 8 oz. firm tofu, cubed
  • ¼ cup celery, diced
  • ¼ cup carrot, diced
  • 1 tbsp. red onion, diced
  • 1 tbsp. jalapeno pepper, diced (optional)
  • ¼ cup avocado mayonnaise
  • 1 tbsp. spicy mustard
  • 2 slices wheat or rye bread, toasted
  • Garlic powder, salt and pepper to taste

Mix all ingredients together. Put between toast with cucumber, tomato, and arugula.

Modification 1: Curried Tofu Salad

Skip the mustard and add diced apple, raisins, walnuts, curry powder, ginger powder, and cayenne powder to taste.

Modification 2: Waldorf Tofu Salad

Skip the celery, carrots, onions, and jalapenos and use grapes, apples, and walnuts instead.

Tofu is a good tuna alternative if you are trying to decrease your mercury intake. Tofu also contains calcium, and the jalapeno will add vitamin C to enhance its absorption. Don’t like spicy? Put tomato on the sandwich instead. The avocado mayo and walnuts will provide you with some

Reach out for more recipes like this and to learn how you can optimize your diet and enhance your performance:

Dr. Theresa DeLorenzo, RD
Nutrition for Optimal Performance

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