Poor Nutrient Absorption & How to Reclaim Good Health


Poor Nutrient Absorption & How to Reclaim Good Health

Reading Time: 6 minutes 8 seconds


Date: 2019-12-04T00:00:00-05:00

Nutrition is a crucial part of overall wellness, health, and even fitness. You may have some clients missing this vital element, even those who "eat clean" or have a generally good diet.

The problem many people overlook is that of nutrient absorption. You can eat all the best foods, but if your body isn't absorbing and using the nutrients from them, you're not getting the benefits. In fact, you could be experiencing some symptoms or health problems as a result.

Make sure your clients understand good nutrition, what it means, how to choose the best foods for a well-balanced diet and long-term health. Also educate them about nutrients in food, what happens when nutrients aren't taken up adequately, and risk factors for poor absorption.

What Are the Harmful Effects of Poor Nutrient Absorption?

If your body is taking in nutrients but not absorbing enough of them, you may end up with deficiencies. The effects are essentially the same as if you weren't eating that nutrient at all. For instance, if your body doesn't use the calcium you consume in your diet, you can have symptoms of weak bones or osteoporosis, as would someone who simply doesn't eat enough calcium-rich foods.

When someone cannot adequately absorb nutrients, of one or more types, and for any reason, doctors call it malabsorption syndrome. There are a number of possible signs of this condition, which vary by individual. All should be cause for concern.

Poor Quality Hair and Nails

Look to your hair and nails to see signs your body isn't getting enough protein. Hair is made of protein, and so are fingernails and toenails. Inadequate protein leads to dry and brittle hair and even hair loss. With poor protein absorption, you'll also see brittle nails.


Fatigue, even after getting enough sleep, is a general sign that can indicate poor absorption of several nutrients. Low iron, low magnesium, and low intake of calories, in general, can all cause persistent fatigue.

Stomach and Digestive Issues

Digestion is often at the heart of the matter when it comes to malabsorption, both as a cause and an effect. Poor digestive health, from irritable bowel syndrome to Crohn's or celiac disease can cause malabsorption and should be recognized as a potential sign of poor nutrient uptake. Uncomfortable bloating and swelling in the abdomen can also indicate malabsorption.

Stool Substance

It's not easy to talk about, but your bowel movements can be important indicators of nutrient absorption. Nutrient deficiencies can lead to diarrhea in particular, but also stools that are unusual in odor and light in color.

Tingling and Numbness

A tingling sensation after sitting cross-legged for a while is normal but frequent, regular tingling or numbness in any part of the body is not. This is an especially important signal for vegans because it may indicate poor intake of vitamin B12, a vitamin mostly found in animal products. Additionally, some people naturally don't absorb this nutrient adequately.

Weight Loss

This can be a tricky one because your clients are often trying to lose weight. But if someone is losing weight too quickly, or is losing without trying and has other symptoms as well, it's a strong indication of a nutrient issue. An even stronger indicator is when weight loss occurs along with fatigue, weakness and difficulty working out, and muscle cramps.

Menstrual Changes

For your female clients, unexpected changes in menstrual cycles can be caused by malabsorption and by inadequate calorie intake. Any changes, such as flow strength, length, or even missed periods should be taken seriously.

Specific Nutrient Deficiencies

The above can be specific but also general and common signs of malabsorption. It's also important to watch for symptoms of specific deficiencies:

  • Iron - fatigue and weakness

  • Thiamine, B1 - weight loss, confusion, memory loss, and fatigue, can be caused by excessive alcohol intake

  • Cobalamin, B12 - fatigue, dizziness, weight loss, poor appetite, pale skin, shortness of breath

  • Vitamin D - poor bone development, frequent bone breaks, osteoporosis

  • Calcium - same as vitamin D and also abnormal heart rhythms

  • Protein - swollen and puffy skin (known as edema), brittle hair and nails, weakness and loss of muscle, increased illness from infections

  • Fat - dry skin, feeling cold, menstrual changes, mental and physical fatigue

Causes and Risk Factors - What's Behind Poor Nutrient Absorption?

Signs and effects of malnutrition could indicate inadequate absorption of nutrients, and there are many potential causes. If any of your clients show troubling signs, make sure they see their doctor right away to be evaluated. An underlying cause can most likely be corrected so they can fix any deficiencies and return to good health.

Intestinal Problems

The majority of absorption of nutrients occurs in the small intestines. Any health problems occurring there can negatively impact the process: ulcers, inflammation, lactose intolerance, damage from trauma or surgery, celiac disease, Crohn's disease, and others. All of these cause actual damage to the inner walls of the intestines, which can reduce absorption.

Liver, Gallbladder, and Pancreas Diseases

Nutrient absorption is complex, and it involves these other organs in addition to the intestines. Some digestive enzymes are produced in the pancreas, for instance. Any disease—chronic pancreatitis, hepatitis, cystic fibrosis, or gallstones—that impacts them can also reduce absorption of nutrients.

Diarrhea and Vomiting

An illness that gives you diarrhea or causes you to vomit can cause malabsorption and malnutrition. Generally, these are acute conditions. You'll recover and your nutrition will return to normal. But there are also chronic conditions that cause these symptoms, including eating disorders, and they present a real challenge for nutrient absorption.


Certain medications affect absorption of nutrients. Examples include the antibiotic tetracycline, some antacids, anti-inflammatory drugs used to treat gout, anticonvulsants for epilepsy, certain diabetes drugs, and cholestyramine, a medication for high blood pressure (1).


Certain aspects of your lifestyle and dietary choices can also impact absorption. Coffee drinkers, for instance, should be aware that excessive caffeine intake can flush nutrients out before they can be absorbed. Unmanaged stress may also reduce absorption.

Alcohol is another issue, and heavy drinkers and those with alcohol use disorders are most at risk. Alcohol actually limits the breakdown and absorption of nutrients. It also blocks the utilization of nutrients that are absorbed. Thiamine deficiency is a particularly dangerous problem for people with severe alcohol use disorder (2).

How to Improve Nutrient Absorption

The most important and first thing your client should do if you suspect they have issues with nutrient absorption is see their doctor. An underlying health issue may be to blame and it is likely treatable.

Once your client has gotten a diagnosis and any necessary treatment, you can help them make smarter food and lifestyle choices for better health:

  • Manage stress in healthy ways, such as meditation, yoga, and exercise.

  • Exercise more. This is an obvious one for you as a trainer, but your clients may not realize how much it impacts nutrients. Exercise helps keep the digestive tract healthy and pushes food through it for better absorption.

  • Get eight to nine hours of sleep each night.

  • Limit alcohol and caffeine intake.

  • Vary foods at each meal. Every meal and snack should include a range of food types. The complex interactions between different nutrients contribute to absorption, so greater variety increases the odds of better absorption.

  • For your vegetarians and vegans, recommend they pair iron-rich foods with those that contain vitamin C. The latter helps make iron more absorbable and usable. They should also avoid drinking tea with food, as the otherwise healthy compounds can limit iron absorption.

  • Include healthy fats in your diet. Clients trying to lose weight may be limiting fats too much. Fat is necessary for the absorption of the fat-soluble vitamins A, D, E, and K.

  • Consider using probiotics to nourish a healthy gut ecosystem.

  • Stay hydrated every day. Adequate fluid levels are needed to move nutrients through the body.

  • Enzyme supplements may help, but make sure your clients talk with their doctors first before trying one.

  • Stop dieting. Some of your clients may be dieting too hard. This could be the root of the problem, so encourage them to increase calorie intake. Then sit down with them and plan a healthy, nutritious diet.

Malabsorption can be a very serious health problem. From brittle nails to severe digestive issues, the consequences can be uncomfortable and even cause long-lasting issues. If you see signs of malnutrition in your clients have a talk with them about a healthy diet and good nutrition. Your intervention right now could help them avoid more serious illnesses in the future.

You'll learn much more about nutrients, absorption, and all things health and nutrition when you complete the ISSA's course to become a certified nutritionist.


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