Most people know that eating the right foods, such as pasture-raised meats, wild-caught Alaskan salmon, organic vegetables and fruits are beneficial to health. You take the time to select, purchase, and prepare the nutritious foods - you are making a major investment in your health! Yet do you ever wonder how much of these nutrients are actually being absorbed by your body?
The body uses nutrients from food for energy, growth, and cell repair, hence, you want to optimize your nutrient absorption. However, nutrient absorption can vary tremendously, depending on many factors. So how do you know if you have poor digestion or malabsorption? If you have a number of the symptoms listed below, you may have a digestion or nutrient absorption problem.
- Belching and/or flatulence
- Feeling full hours after a meal
- Heartburn or acid reflux
- Constipation and/or diarrhea
- Gallbladder disease
- Food allergies
- Weak, cracked finger nails
- Iron deficiency
- B12 deficiency
- Skin problems, such as acne, eczema, dermatitis, psoriasis, and rosacea
Digestion involves the disassembly of the food you eat, its movement through the digestive tract, and the chemical breakdown of the large molecules of food into smaller molecules. Digestion begins in the mouth when we chew and swallow, and ends in the small intestine.
One of the most important factors in nutrient absorption is digestive enzymes, which break the chemical bonds in proteins, fats, and carbohydrates and turn these compounds into microscopic substances that can be used at the cellular level. Without these enzymes, nutrients will never reach the cells that need them and they will merely get passed out of the body.
Chewing is stage one of proper digestion
Digestion starts in the mouth with saliva and the digestive enzyme amylase which breaks down starches into simple sugars. Coupled with the chewing action, the food is predigested into smaller pieces and a semi-liquid form, making it easier to digest when it reaches the stomach.
- Most people do not chew their food thoroughly. When large particles of improperly chewed food enter the stomach, it may remain undigested when it enters the small intestine. There, bacteria will begin to break it down, potentially leading to gas and bloating, diarrhea, constipation, abdominal pain, cramping, and other digestive problems.
Stomach acid is key to stage two of good digestion
The food moves from the mouth down the esophagus, through a one-way valve called the esophageal sphincter into the stomach. When it gets there, it is the stomach's job to temporarily hold the food, churn and mix it, and begin to break it down. Depending on the contents of the meal, this process takes between 40 minutes to a few hours.
Glands in the stomach lining produce gastric juice which contains stomach acid (hydrochloric acid or HCL) and the enzyme pepsin that digests protein. Stomach acid, being extremely acidic, sterilizes the food and destroys pathogenic bacteria and parasites, as well as their eggs and larvae.
- Aging, stress, poor diet and lifestyle habits all contribute to a decline in stomach acid production.
- Not having enough stomach acid may allow bacteria and parasites to survive and proliferate. About two-thirds of the world's population have a type of bacteria Helicobacter pylori (H. pylori) that live in their digestive tract. After a number of years, H. pylori may cause ulcers in the lining of the stomach or the upper part of the small intestine.
- Low stomach acid gives rise to low pepsin production, which means you cannot digest protein properly. As a result, the food stagnates and ferments, setting you up for digestive problems.
- In most cases of heartburn and acid reflux, it is the result of too little stomach acid, not too much. When the stomach is not acidic enough despite it being full of food, the esophageal sphincter may fail to stay completely closed, leading to heartburn and acid reflux.
Bile, pancreatic and small intestinal enzymes complete the last stage of digestion
The partially digested food in the stomach called chyme passes through the pyloric valve at the bottom of the stomach into the duodenum, which is at the top end of the small intestine. The muscles of the small intestine mix the chyme with digestive juices from the liver, pancreas, and small intestine.
The liver produces bile which is stored in the gallbladder between meals. When you eat, the gallbladder squeezes bile through the bile ducts which connect the gallbladder and liver to the small intestine. Bile mixes with fat and dissolves it, allowing the pancreatic and intestinal enzymes to complete its digestion.
The small intestinal enzymes combined with pancreatic enzymes and bile complete the digestion process, turning the proteins, fats, and carbohydrates into usable components for the body.
Absorption of nutrients
The wall of the small intestine is covered with billions of microscopic finger-like projections called microvilli, which increase the absorptive surface by about six times. Each villi contains a lymph vessel surrounded by capillaries. It is here that nutrients are absorbed into your bloodstream and brought to the individual cells in the body.
- Hence, if the microvilli are damaged, your nutrient absorption will be immensely compromised. Much research has been done in this area. They found that inflammation in the body, either systemic or local, undermines the function of the small intestinal lining. The following are some conditions that are associated with this problem -
- Celiac disease and gluten sensitivity
- Autoimmune diseases
- Food allergies and sensitivities
- Inflammatory bowel disease
- Small Intestinal Bacterial Overgrowth (SIBO)
- Bacterial, yeast, and parasitic infections
- Heart disease
Last but not least is the colon or the large intestine. Little nutrient absorption happens here. Its main job is to absorb the excess water and recycle it back into the bloodstream. As the waste moves along, it dries and forms stool which is then excreted.
Ways To Improve Nutrient Absorption
- Chew your food slowly. Digestion begins in the mouth.
- If you have some of the digestive symptoms mentioned above, take a digestive enzyme with HCL at every meal, which will help alleviate much of your discomfort. (The only exception is when you have a H. pylori infection. In this case, you want to eliminate the bacteria before starting this protocol.) Take enough enzymes and HCL until your symptoms disappear. If you take too much HCL, you will feel a warm, burning sensation in your stomach. Back down on the dosage at your next meal.
- Drink liquids 15 minutes prior to a meal. Too much liquid with food can dilute the stomach acid especially if your production is already low.
- If you have any of the inflammatory conditions mentioned above, restore the health of your intestinal lining by addressing the underlying causes of your inflammation. Once the intestinal lining function has been restored, many of these conditions can potentially go into remission.
- Incorporate fermented foods (such as sauerkraut, kimchi, komucha, and kefir) into your daily diet. Or alternatively, take a probiotic supplement everyday.
- Avoid excessive alcohol. Overconsumption can compromise nutrient absorption by decreasing the secretion of digestive enzymes and damaging the intestinal lining.
How To Get The Most Nutrition From Your Food
- Eat locally grown produce soon after they have been picked. The longer they are separated from the soil, the more nutritional value they lose. However, do not discount frozen vegetables even though they have lost some vitamin C. It is still better than not eating vegetables at all.
- Soak grains, beans, nuts, and seeds to reduce phytic acid which can potentially block the absorption of minerals (like calcium, copper, iron, magnesium, phosphorus, and zinc) and inhibit essential digestive enzymes. Soak raw nuts and grains in warm, filtered water for up to 12 hours. Keep the bowl at room temperature. Drain and rinse afterwards.
- Heat breaks down and destroys the water-soluble B and C vitamins in vegetables. Therefore, it is beneficial to incorporate some raw vegetables into your diet. However, if you do cook them, these are the best ways to preserve their nutrients -
- blanching (cooking in boiling water for a short time, then plunging into iced water to stop the cooking process)
- Certain foods deliver more nutrients when cooked. They include -
- tomatoes (lycopene)
- broccoli, carrots, red bell pepper, spinach, sweet potato, tomatoes, and winter squash (beta carotene)
- heat denatures protein in eggs and meats, making them easier to digest.
- Some people are more prone to getting calcium-oxalate kidney stones. Oxalates are naturally-occurring substances in many foods, like black and brown millet, sesame seeds, soybeans, almonds, cashews, peanuts, spinach, Swiss chard, and beet greens. Instead of avoiding oxalate-rich foods, eat them with calcium-rich foods (not supplements). This way, the oxalate and calcium will bind in the intestine, hence, preventing them from being absorbed into the bloodstream and getting transferred to the kidneys.
- Fat-soluble nutrients in vegetables require fat to be properly absorbed. They are vitamins A, D, E, and K. Therefore,
Vegetables like -
- carrots, sweet potatoes, winter squash (vitamin A)
- mushroom (vitamin D)
- asparagus, spinach, and Swiss chard (vitamin E)
- broccoli, kale, and spinach (vitamin K)
are much better to be eaten with healthy fats like -
- animal fats (from pastured-raised animals)
- coconut oil
- olive oil
- nuts and seeds
- Pair iron-rich plant foods with vitamin C. Iron from non-meat sources is called nonheme iron. Nonheme iron is not as well absorbed as heme iron which comes from red meats like beef, lamb or dark chicken meat. To enhance the absorption of nonheme iron, pair these iron-rich plant foods -
with vitamin C -
- chili peppers
- lemon juice
- Pair foods rich in iron and zinc with sulfur. Sulfur binds with these minerals and enhances their absorption. Foods like -
- beef, liver, and turkey (iron)
- beef, oysters, and turkey (zinc)
will go very well with these high sulfur foods -
- egg yolks
Carol Chuang is a Certified Nutrition Specialist. She has a Masters degree in Nutrition and is a Certified Gluten Practitioner. She specializes in Metabolic Typing and Functional Diagnostic Nutrition.