Can Obesity Cause Malnutrition? Malnutrition in Obesity Explained

Find out how malnutrition may occur in people living with obesity and how to prevent it, as well as other tips for achieving good health.
Medical Reviewer: Julia Axelbaum, RD
Published on: June 6, 2023
Updated on: March 5, 2024

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When we think of malnutrition, we don’t typically associate it with obesity. However, it’s important to recognize that malnutrition, which refers to a lack of essential nutrients, can occur not only in those who don’t have enough to eat but also in individuals struggling with obesity. Surprisingly, whether you are underweight or overweight, your body can still suffer from undernourishment.

Obesity is a complex disease state which can cause multiple processes in the body to become imbalanced which can result in challenges absorbing nutrients. An imbalanced diet, which can contribute to obesity, can also exacerbate malnourishment issues. When your body isn’t properly nourished you can have a number of health issues like anemia, poor eye-sight, general weakness, and fatigue among  others. Obesity can mask these issues as we tend to attribute them solely to the visible issue: too much weight. This can lead to long-term health problems stemming from undiagnosed vitamin and/or mineral deficiencies. So are all individuals who struggle with excess weight malnourished? Not necessarily; let’s look at how malnourishment and obesity can co-exist and some of the risk- factors associated with this combination of health conditions. 

Reasons Why People Living with Obesity May be Malnourished

Though obesity itself does not cause malnutrition, there are a cascade of consequences leading to and stemming from weight gain that can affect nutritional status. In fact, there are more individuals living with obesity who struggle with malnourishment than those of a normal weight. Poor dietary choices are often the common theme behind weight imbalance but there are other, lesser known factors that play a role as well. Let’s look at some of the common reasons why someone with obesity may be malnourished.

Too much processed foods

Processed foods are prevalent in our culture and they do us no favors when it comes to weight management and consuming a healthy diet. Processed foods include ingredients added by the food industry to give the product a longer shelf-life, make it look better, or improve taste. These could include hydrogenated oils, high-fructose corn syrup, flavoring agents, and emulsifiers. The problem with processed foods is that they are often calorie-dense but not nutrient dense so they bring an abundance of fat, salt, and sugar but not much else. These foods taste good, are often inexpensive, and are easy to eat; but do little for satisfying hunger or providing nourishment.

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Not enough fiber

Fiber is a nutrient found naturally in plants that cannot be fully digested by the body. This essential nutrient helps regulate digestion, promotes feelings of fullness, and reduces risk of cardiovascular events by helping to reduce overall cholesterol levels. Because this nutrient is found primarily in fruits and vegetables and other whole grains, most Americans are getting less than half of the recommended fiber intake. The Recommended Dietary Intake (RDI) for fiber stands at 38 grams per day for men 50 and younger and 30 grams for men 51 and over. For women, the goal is slightly lower at 25 grams per day for women 50 and younger and 21 grams for women 51 and over. The average American, however, gets only 10-15 grams of fiber each day which is associated with higher hunger levels and risk of constipation. A diet lacking in fiber is generally linked to a diet low in fruits, vegetables, and whole grains which can increase the risk of malnourishment as well. 

Lack of nutritious meal planning

Meal planning can be difficult when busy schedules make it more difficult to find time to shop for food and cook at home. Lack of meal planning can ultimately lead to more meals on-the-go, including convenient fast foods and pre-packaged food items. These foods are often higher in total calories, fat, salt, and sugar while being low in fiber, protein, and vitamin and mineral content. This discrepancy can further the issue of malnutrition in a population that may already be struggling with or at risk of obesity. 

Digestive issues and poor nutrient absorption

Some individuals have existing issues that can contribute to malnutrition such as digestive issues and/or nutrient absorption issues. These issues can stem from diseases such as ulcerative colitis, Celiac disease, or previous bariatric surgery. When the body cannot properly absorb nutrients, overall nourishment declines. This is often an issue with absorption of vitamins and minerals but can also lead to problems with absorption of macronutrients (carbohydrates, proteins, and fats) which can lead to  muscle mass loss and overall weakening of the body.

Excessive alcohol consumption

When consumed in moderation, alcohol can be part of a healthy diet. However, when alcohol is consumed in excessive amounts, it can be difficult to get the nutrients needed to support a balanced diet. Alcohol is a toxin, so the body will process alcohol first and any other nutrients second. Alcohol intake can also lessen inhibitions so consumption of junk foods and foods high in fat, sugar, and salt can often be increased. Empty calories mean little nourishment from those food sources which can worsen or contribute to malnourishment. 

Mental health disorders

It is estimated that more than 1 in 5 American adults live with a mental health disorder.While there is no research that shows that certain foods cause mental illness, there is research that shows that an unhealthy diet can worsen symptoms of an already present mental health disorder. Foods high in fat, sugar, salt, and those that are highly processed can decrease gut health. Our gut is where 95% of our serotonin is produced. Serotonin is a hormone that influences both mood and GI health. This can be a double edged sword: When mood is negatively influenced and markers of depression and anxiety are high, eating habits can worsen, leading to a higher intake of junk foods and lower intake osf nourishing foods thus worsening or contributing to malnutrition. 

Signs and Symptoms of Malnutrition

Recognizing the signs and symptoms of malnutrition is crucial in identifying potential nutritional deficiencies and addressing them promptly. Understanding these symptoms can help individuals and healthcare professionals identify the need for proper nutritional support and interventions to ensure overall health and well-being.

Dry hair and skin, brittle nails

Though dry hair and skin and brittle nails can seem like issues that only run skin deep, they can actually be signs of a bigger problem. When the body isn’t nourished properly it will start to pull resources away from areas of our body that are not central to survival such as our hair, skin, and nails in favor of sending them to more vital areas of the body such as our organs. Diets low in nutritious foods such as fruits, vegetables, whole grains, dairy, and protein can lead to deficiencies in iron, certain B-vitamins, and other micronutrients that can worsen skin, hair, and nail health as well.  

Loss of muscle mass

 Muscle mass is an important part of body composition. We know muscles are essential for movement, strength, and mobility but they are also an integral part of a healthy metabolism. Muscles require more energy than other parts of our body and thus “cost” more calories per day than fat mass does. The higher the muscle mass an individual has the more calories their body burns while at rest. A diet high in processed foods and low in overall protein can lead to malnourishment as well as loss of muscle mass. This leads to a slower metabolism and a weaker body in general. 

Slow wound healing

Wounds can occur for a number of reasons such as an injury from an  accident, lack of movement leading to pressure sores, or high blood sugar leading to diabetic ulcers following an injury. In all of these cases, proper nutrition is essential  for healthy wound healing. When malnutrition is present, essential vitamins and minerals for wound healing may be low or absent. Nutrients such as protein, vitamin E, and vitamin C are needed for optimal wound healing. In a malnourished individual wounds may heal slowly or not at all. 

How to Avoid Malnourishment While on a Diet

Restrictive weight loss programs, while aimed at achieving rapid weight reduction, can inadvertently contribute to malnourishment. By severely restricting calorie intake or eliminating entire food groups, these programs may fail to provide sufficient essential nutrients for optimal bodily function. Restrictive approaches can lead to imbalances in vitamin and mineral intake, resulting in potential deficiencies and malnutrition. Follow these tips to ensure your body is getting the nourishment it needs: 

Eat nutrient-dense, whole foods

A diet rich in fruits, vegetables, whole grains, lean meats, healthy fats, and low-fat dairy includes a wide variety of essential vitamins and minerals that support a well-nourished and healthy body. Anytime we can choose a whole food instead of a processed option (think a banana over. banana chips or a lean chicken breast over chicken nuggets), we are more likely to be better nourished and avoid malnutrition.

Monitor your calorie intake

There is no shortage of apps focused on diets, weight loss, and healthy eating. Though monitoring caloric intake is not everyone’s cup of tea, it can be a helpful tool to gain insight into not only the quantity of calories, but also the quality of the calories you are consuming. Apps like My Fitness Pal are free and help you better understand your consumption of protein, fiber, and vitamins/minerals. Tracking calories and food intake can be a great tool to use to make changes in your diet if you notice a nutrient is too high or low. When our diet quality is high, it is easier to avoid malnourishment. 

Drink enough water

Our body’s demand for water is both fluid (pun intended) and static. Static from the standpoint that daily hydration is essential, but fluid in the sense that the amount needed can and will be impacted by numerous factors including age, activity level, environment (heat, humidity, etc.), and medications among others. Drinking enough water can help keep you hydrated and in better control of your hunger. If your hunger is well controlled it can be easier to make healthier choices and support a well-rounded diet. Hydration is just one of many tools in avoiding malnourishment. 

Lose Weight AND Get All the Nutrients

Malnutrition can affect people of all body types, including those who struggle with excess weight. The complexity of obesity and its associated imbalances can contribute to poor nutritional status. Factors such as a diet high in processed foods, inadequate fiber intake, lack of nutritious meal planning, digestive issues, excessive alcohol consumption, and mental health disorders can all play a role in malnourishment. To avoid malnourishment it is important to prioritize nutrient-dense, whole foods, monitor calorie intake, and drink enough water. 

Consulting with a medical professional is the best way to ensure proper nutrition and address any underlying issues. At FORM, we understand the complexities of weight management and offer personalized solutions to help you achieve sustainable weight loss. Take the next step towards optimal health by scheduling a call, sending a message, or taking our quiz to find out if you are eligible for FORM.

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