“You are what you eat” is a famous saying my parents often said to me as a child to encourage me to eat better. As a dietitian with a passion for gut health, I now understand the many inaccuracies of that statement. Clearly...you are not what you eat, you are what you eat, digest, and absorb. It’s possible to eat a wide variety of highly nutrient-dense foods but not get the full benefit of these foods simply because they pass right through you. What you eat is the easy part these days, it's the digestion and absorption that many of us need to work on to reap the full benefits of a healthy diet.
Not absorbing nutrients is comparable to not getting them in the first place. Nutrients can’t support the body if they never truly make it into the system to support health and do the work they need to do. A lack of essential nutrients can lead to serious health concerns. According to a recent study published in the journal, Nutrients, researchers found that “Nearly one-third of the U.S. population is at risk of deficiency in at least one vitamin, or has anemia.” The top five most common nutrient deficiencies in the U.S. are for Vitamins B6, B12, C, and D, and the mineral iron.
The digestive system, put simply, is how the body takes essential nutrients from food and absorbs them so they can be used for growth, maintenance, energy, healing, and overall good health. For example, Vitamin A has to reach the eyes to prevent night blindness, and Vitamin C has to make it to the skin to heal wounds. The same goes for iron in your blood and energy levels, and calcium for your bones, muscles, and teeth. Before nutrients can get to their destination, they first need to be removed from the food, digested, and absorbed into the body to ultimately support health.
In this blog post we’ll go over some of my pro tips on how to make nutrients more absorbable by two mechanisms: enhancing digestion and food pairing. But first, why are some nutrients hard to absorb?
Why some nutrients are harder to absorb
Several essential nutrients are required in the diet to maintain good health. This includes macronutrients (e.g., protein, carbohydrates, and healthy fats) and micronutrients (e.g., vitamins and minerals). Digestion and absorption of nutrients can be challenging even with the healthiest of diets, as many variables can interfere, such as: stress, inadequate chewing, food sensitivities, reduced stomach acid, and decreased pancreatic enzymes to name a few.
Fun fact: How much of a nutrient is absorbed and can be used or stored in the body is called nutrient bioavailability. This describes how available the nutrient is for our biological use.
There are three main steps to digesting the food you eat: breaking it down, absorbing the nutrients, and eliminating the rest. That’s why your digestive system provides a long, diverse journey for food to travel once it’s eaten. For example, your stomach is full of digestive juices (e.g., acid, enzymes) to break food into smaller pieces. Then, as your food starts moving through your small intestine, your liver and pancreas add alkaline bile (to neutralize the acid), as well as other enzymes to break down other components of food. Your small intestine is responsible for most—but not all—of the absorption of nutrients into your body. The final journey is through the large intestine that is home to your friendly gut microbes (helpful bacteria and other tiny microorganisms). These microbes can break down (or ferment) some of the toughest nutrients that have made it this far intact (some fibers). The large intestine also absorbs some nutrients and water.
Whatever nutrients don’t get absorbed—because they weren’t broken down small enough, or perhaps they were complexed with anti-nutrients, or because the digestive tract itself couldn’t do its best work—is eliminated as waste. It’s natural and healthy to eliminate a lot of what you’ve eaten, but ideally the waste should have very little nutrition left in it. You want most of the essential nutrients to be absorbed so your body can use them to complete the many tasks it's required to keep you functioning optimally. If you are inadequately digesting your food, you may experience bloating, belching, gas, undigested food particles in your waste, and irregular bowel movements. If this is you...we need to chat today.
Despite the diverse and complex processes that your body uses to absorb and digest as many nutrients from foods as possible, sometimes it can use some help. Before you reach for probiotics or digestive enzymes, run a functional stool test with us to get to the root cause first. Some people have food intolerances or digestive issues that result in malabsorption of certain nutrients - one example would be Celiac Disease. Plus, there are some nutrient-nutrient interactions and anti-nutrients found in foods that can reduce your ability to absorb them.
The good news is research shows that there are some very interesting things that can increase nutrient bio-availablity, naturally. By eating certain nutrients together—or apart, or certain foods cooked—or raw, you can enjoy the same foods, but in a more nutritionally efficient, bioavailable, way.
I'm eating a healthy diet, so why do I still feel like crap?
Here are some simple strategies to get more nutrition from the foods you enjoy.
Absorb more Vitamin C: Enjoy these foods fresh and raw
Vitamin C is one of the most common vitamin deficiencies in the U.S. Foods that are rich in Vitamin C include fruits and vegetables. Some of the highest sources of Vitamin C are in bell peppers, citrus fruits (and their juices), kiwis, broccoli, and strawberries.
Vitamin C is an antioxidant that is water-soluble and destroyed by heat. This means that the Vitamin C levels are highest when the food is fresh and raw (or cooked as little as possible). To maximize the Vitamin C levels in your fruits and vegetables, try to eat them as fresh and raw as possible. If you enjoy them cooked, do so minimally by lightly steaming or microwaving them.
One of my favorite ways to get a healthy dose of Vitamin C is with a nutrient dense smoothie, like this Ginger Berry Smoothie recipe here.
Absorb more iron: Enjoy iron-rich foods with—and without—these
Iron is the most common mineral deficiency in the U.S. Some of the most iron-rich foods are meat, seafood, beans and lentils, liver, spinach, and tofu. Also, some breads and cereals are fortified with iron. But, not all iron-rich foods are equal. Iron is found in two different forms: heme (in animal-based foods) and non-heme (in plant-based foods). Heme iron is more bioavailable and more easily absorbed than non-heme iron. This means that the iron in plants is more difficult to absorb, but there are some simple tips that you can use to absorb more.
Iron absorption can be enhanced when consumed with Vitamin C-rich foods and away from tannin-containing drinks like tea and coffee. This means, enjoy your meat, beans, lentils, spinach, or tofu with a Vitamin C-rich food in the same meal. For example, add some bell peppers, orange wedges, or berries to your spinach salad. And enjoy your tea or coffee—not with, but—between your iron-rich meals.
Absorb more fat-soluble essential Vitamins A, D, E, and K
Vitamin A is found in liver, seafood, eggs, and fortified dairy. Pro-vitamin A (beta-carotene) is found in fruits and vegetables, especially orange ones like sweet potatoes and carrots, and dark green leafy ones like spinach and kale. Because of the way beta-carotene is stored in the plant cells, not all of it is as bioavailable as Vitamin A in animal-based foods. Unlike with Vitamin C, Vitamin A is fat-soluble and becomes more bioavailable when orange and dark green plant-based sources are cooked.
Vitamin D is essential for bone health because it promotes absorption of calcium and is needed by bone cells for growth and repair, Vitamin D also helps reduce inflammation and helps to regulate the immune system and carbohydrate metabolism. Known as the sunshine vitamin because your skin makes Vitamin D when exposed to UV light, Vitamin D is also naturally found in a few foods. These foods include seafood, mushrooms exposed to UV light, egg yolks, and some fortified dairy.
Vitamin E is an antioxidant vitamin that is necessary for protecting cells from oxidants to prevent or delay chronic diseases. Vitamin E is also essential for your immune system. Foods with high levels of Vitamin E include whole grains, nuts and seeds, and their butters and oils (e.g., wheat germ oil, sunflower oil, peanut butter).
Vitamin K comes in two forms: K1 is in dark green leafy vegetables, broccoli, soy, and herbs. Vitamin K2 is mostly made by bacteria, so it’s found in fermented foods like yogurt, cheese, and sauerkraut. Vitamin K is essential for proper blood clotting and bone metabolism.
These four fat-soluble vitamins can be fairly bioavailable on their own, but a simple tip can help enhance absorption even more: get enough healthy fat. This means cooking your vegetables with a bit of healthy oil or pairing them with a nutritious dip or dressing to help you absorb more of these essential fat-soluble vitamins.
Be sure to pair fat soluble vitamins with healthy fats, check out this recipe for our delicious mushroom and egg breakfast muffins here.
Absorb more calcium: Be sure to have a regular supply of Vitamin D
The largest sources of calcium in the North American and European diets is from milk and dairy products. You can also get calcium from fruits and vegetables (e.g., kale, spinach, broccoli), as well as mineral water. Some of the plant sources of calcium have lower bioavailability because they contain anti-nutrients like oxalate and phytic acid. The amount of calcium absorbed from these foods is increased with Vitamin D intake. While you don’t need to get Vitamin D in the same meal as a calcium-rich one, getting enough vitamin D every day is key—whether that means eating Vitamin D-rich foods with a bit of healthy fat or going outside in the sun.
Note: See the section above on fat-soluble vitamins for more information about Vitamin D.
Now that you know why you are eating healthy, but still feeling like crap, what are you going to do about it?
Healthy eating is more than consuming nutritious foods, it’s also about digesting and absorbing the nutrients from those foods so they can be used in your body. With a few simple tips as outlined above, you can now get more benefits when you enjoy the same nutritious foods you usually do.
One way to ensure that you eat healthy and feel ah-mazing, is to follow our meal plan. Check out this free 5 day meal plan - with no strings attached! Give it a try here.
Optimal nutrient absorption requires the right diet and a healthy digestive tract. If you have concerns about your nutrition plan or digestion, we are here to help. Schedule a NO CHARGE Discovery Call today to learn about functional lab testing, customized meal plans, and more.
In good health,
Kristie + Rebecca
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