When we eat a meal, our thoughts don't often go beyond "damn, this is tasty" or "I'm so hungry". The way food travels down to our digestive system, gets broken down into molecules and used for various bodily processes doesn't usually cross our minds.
Truth is, eating is way more than just putting food in our mouth, and what we do outside of eating the food can actually have an impact on the way our body absorbs its nutrients.
Fortunately, there are ways to boost the body's ability to absorb nutrients, helping us to get the most out of food and supporting optimal body function.
Why are nutrients from foods important?
"Nutrients are required for important biochemical reactions within the body which are vital for our health and wellbeing," nutritionist Fiona Tuck told HuffPost Australia.
As Jayta Szpitalak, nutritionist and founder of Fermentanicals, explained, our bodies function from a combined intake of micronutrients, macronutrients and water.
"This is made up of protein, carbohydrates, fats, vitamins, minerals and, of course, water," Szpitalak said.
"By eating a balanced and well-rounded diet, we nourish our bodies -- providing our bones with calcium to keep them strong, our muscles thrive off our protein intake, and our organs function from the vitamins and minerals derived from fruits and vegetables."
If we do not eat a broad variety of nutrients then we are at risk of becoming low in certain nutrients, which can affect these biochemical reactions in the body.
"We need nutrients for healthy functioning of all of our organs -- heart, brain, liver, kidneys and thyroid, to name just a few," Tuck said.
"Symptoms [of nutrient deficiencies] may be subtle, such as fatigue, dull hair or skin, but if left for years it may manifest into more serious ailments."
How does the body absorb nutrients?
In order for nutrients to be absorbed, food must undergo chemical and mechanical digestion.
"After food is consumed through our mouths, they are met with digestive enzymes which help break down the food into different molecules," Szpitalak told HuffPost Australia.
"This breaks down the macro and micronutrients. For example, our protein is broken down into various amino acids, and carbohydrates are turned into glucose for energy or storage.
"Once the food is broken down into the vital nutrients, it travels down to the small intestines and is absorbed into the blood stream. The circulatory system then takes over and transports the nutrients to the various parts of the body that need them. Whatever is not used is distributed to either storage or waste."
For this nutrient absorption process to work optimally, we need a healthy digestive system, Tuck explained.
"If our digestion or gut health is not good we may not absorb nutrients well. Factors such as thoroughly chewing food, good levels of hydrochloric acid, good gut bacteria and good cell integrity of the gut are important for nutrient absorption," Tuck said.
What factors can negatively affect nutrient absorption?
There is a whole host of factors which can negatively affect our body's digestion and nutritional absorption from foods, including gastrointestinal issues such as IBS and coeliac disease, as well as a diet high in sugar and processed foods.
"Processed foods are low in nutrients, and high sugar foods can actually rob the body of nutrients, particularly magnesium," Tuck said.
"Certain medications such as antacids, blood pressure medications, antidepressants and hormone medications can interfere with nutrient levels in the body."
Stress and alcohol consumption can also play a part in digestion and nutrient absorption.
"Stress increases our nutrient requirements -- particularly vitamin C, the B vitamins and magnesium -- which can lead to irritability and fatigue when these nutrients become depleted," Tuck said.
"Alcohol consumption is linked to a reduction of digestive enzymes, so people who drink heavily may not be able to break down the nutrients from the foods in the first place," Szpitalak added.
If you experience changes in your stool, digestion, energy levels, and the condition of your hair, skin and nails, check in with a GP to find out if you have any nutrient deficiencies.
How to boost nutrient absorption
Providing you don't have underlying medical conditions as outlined above, there are a few ways to improve your nutritional absorption.
1. Eat a variety of foods in one meal
To get a combination of nutrients, focus on including various colourful foods in your meals -- for example, a salad with roast vegetables or brown fried rice with carrot, greens, capsicum, zucchini and celery.
"Eat a variety of different foods every day and avoid eating the same foods -- for example the same breakfast every day. Mix it up. This ensures a broad variety of nutrients," Tuck said.
2. Pair vitamin C-rich foods with iron
Particularly for people consuming plant-based iron sources (legumes, tofu, dried fruit), pairing these with vitamin C-rich foods helps to convert the nonheme iron into a more bioavailable form.
"Eat vitamin C-rich foods such as oranges, capsicums, chilli, cauliflower and brussels sprouts, with iron-rich foods (such as legumes and red meat) to increase iron absorption," Tuck said.
3. Include healthy fats with each meal
"Vitamins such as A, D, E, and K need healthy fats to efficiently absorb as they are all fat soluble," Szpitalak said.
As such, you can use oil-based salad dressings such as flaxseed or olive oil to enhance the absorption of fat soluble vitamins from your vegetables.
"Adding nuts, seeds and avocados to salads and meals are also a wonderful way to enhance your nutrient absorption," Tuck said.
4. Take a probiotic
"Nourish your gut. Especially if you do have issues related to digestion, such as IBS or constipation, it's best first to get a handle on that," Szpitalak said.
"You can do this by populating your gut with healthy bacteria either via probiotics or probiotic-rich foods such as kefir, sauerkraut and kombucha."
5. Avoid drinking tea at mealtimes
Although tea contains healthy polyphenols and other compounds which may reduce the risk of developing chronic diseases, these compounds are also known to inhibit iron absorption.
"Avoid drinking tea and coffee with meals as this can inhibit the absorption of many vitamins and minerals," Tuck said.
6. Take a break from caffeine and alcohol
"Alcohol and diuretics [like coffee] not only lesson the number of digestive enzymes in your system, it also damages the cell linings of the stomach and intestines, making it harder for the nutrients from digestion to enter the bloodstream," Szpitalak said.
"Instead, try to incorporate fruits and vegetables that have natural digestive enzymes such as pineapple, papaya or various mushrooms."
7. Manage stress levels
"Believe it or not, stress negatively affects digestions as well," Szpitalak said. "The cortisol felt by the body during stress slows down digestion and food is left in the system undigested.
To help, try deep diaphragmatic breathing which can relieve stress and get the digestive system going.
"This one important factor can make or break our digestion," Szpitalak said.
"When you haven't had enough fluids or water, you immediately see a difference in your stools. Our digestive system is reliant on our level of hydration as our blood cannot transport nutrients without enough water in our system."