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About one in ten patients gets infections

- and lack of nutrients is an overlooked problem

 About one in ten patients gets infectionsAccording to the statistics, far too many patients contract an infection while being hospitalized in a Danish hospital. This has enormous human and economic costs that need to be addressed. Hospital infections are not only a consequence of poor hygiene, it actually turns out that 40 percent of the patients are malnourished to some degree, which impairs their immune system and makes them an easier target for infections. Lack of vitamin C, vitamin D, selenium, zinc, and iron seem to be the big and overlooked problem.

They say that it requires exceptionally good health to be a hospital patient, and that is putting it mildly. Every year, somewhere between 60,000 and 100,000 Danes are believed to contract an infection during their hospital stay. The problem appears to be worst in the hospitals in the Region of Southern Denmark, where 8-10 percent of patients contract an infection while being hospitalized.
Many patients with bacteria in their bloodstream have had a catheter inserted into a blood vessel or the bladder, and the bacteria are transmitted through the catheter. Of course, there is also focus on regular hygiene and the fact that some of the most contagious and antibiotic-resistant bacteria are often found in hospitals.
Since 2013, Danish hospitals have worked systematically to reduce the number of hospital infections, but the number has not gone down. The countless infections come with enormous costs in terms of disease, complications, sick leave, and compensations. In worst case, these infections can be lethal. It takes extraordinary measures to fight hospital infections, and it is advisable to take a closer look at the nutritional status of the patients, especially the older patients, who occupy the majority of beds. However, it is also important for the younger patients to get sufficient amounts of the nutrients that are important for the immune system.

  • WHO estimates that hospital infections cause at least 37,000 European deaths annually
  • This estimate ranks hospital infections as number five on the list of most frequent death causes

Malnutrition is a huge, concealed problem for society

Malnutrition mainly affects older and diseased people, addicts, and those with eating disorders. Twenty percent of patients are already more or less malnourished at the time when they are admitted to the hospital. Hospital meals don’t exactly improve the situation. Around 40 percent of the patients in hospitals are malnourished or risk becoming it. Patients in hospitals and nursing homes usually receive medical care for their secondary diagnoses. They may receive a diet plan, but it is not always followed up, which means that the malnourishment becomes a much greater threat to the health of these patients, because they don’t get enough calories and essential nutrients. This also increases the risk of infections and complications.
The reason why doctors and nurses generally lack insight and experience with malnourishment is that their training only has limited focus on nutrition. Moreover, nutrition has low priority compared to medical therapy and surgery.
It would be a good idea to improve the educations in this area and to screen patients for malnourishment. Blood testing could help identify deficiencies of vitamin D, iron, zinc, folic acid, and vitamin B12, so that these problems could be corrected immediately.


A study from Aalborg University Hospital shows that only around 50 percent of patients get have the minimal amount of calories. The same is the case in other hospitals.
Many patients are malnourished after being discharged from the hospital
Malnourishment is estimated to cost Danish taxpayers around DKr 6 billion annually and far too little is done about the problem.

Vitamin and mineral deficiencies are especially common among the older

More than 50 percent of people aged 65 years and older have low blood levels of vitamin D, which is especially important for the immune system. Lack of vitamin B12, folic acid, and iron is also common. This was the conclusion of a larger study carried out by researchers from Helmhotz Zentrum in Munich, Germany. There seems to be a similar picture among older people in Denmark, as well. This is critical because the ageing population is increasing
The lack of essential nutrients compromises the immune system, leaving the older people increasingly vulnerable to infections and a host of different diseases. The study was published in the science journal Nutrients in 2017.

Tobacco, alcohol abuse, and medical drugs also deplete the body of vital nutrients

Vitamin C strengthens your immune system’s storm troops

The white blood cells of our immune defense contain large quantities of vitamin C, which is essential for the storm troops and their ability to fight bacteria and virus and prevent them from causing disease. Vitamin C is also important for the production of interferons, which are signaling substances that cells use to communicate.
The reference intake (RI) level for vitamin C is 80 mg for adults, but this does not seem to be sufficient for protecting against infections. Physical and mental stress, infections, smoking, and a large consumption of sugar, alcohol, and narcotics can increase your need for vitamin C, and so can sleeping drugs and birth control pills.

Can you get enough vitamin C from your food?

It is generally a good idea to consume plenty of fresh fruit and other useful vitamin C sources, but in case you did not know it, you need to eat around 13 oranges or 60 apples to get the same amount of vitamin C as you would get from taking a tablet with 750 mg of non-acidic calcium ascorbate

Your immune system cannot function without vitamin D

Danish scientists have discovered that the white blood cells called T cells are totally dependent on vitamin D. Our main source of vitamin D is the sun during the summer period. The amount of vitamin D that we get from our food is minimal, and regular multivitamins contain too little vitamin D to make much of difference in terms of immunity. Some of the factors that put many of us at risk of being vitamin D-deficient, even during the summer period, is spending too much time indoors, ageing processes, having dark skin, overusing suncream, being overweight, having type 2 diabetes, and using cholesterol-lowering medication. A vitamin D deficiency goes unnoticed to begin with, but it eventually affects the immune system and makes us very vulnerable to infections. Vitamin D is lipid-soluble, so the best way to take it for absorption and utilization is when it is bound to oil in soft-gel capsules.

A blood test can show your vitamin D status

Vitamin D levels in the blood are measured as 25-hydroxyvitamin. The official (lower) threshold level is 50 ng/ml, but many researchers find that this is insufficient and recommend as much as 75-100 ng/ml for optimal disease prevention.

Low dietary selenium intake harms your thymus and the white blood cells

Selenium is necessary for supporting around 30 different selenoproteins that control energy turnover, the metabolism, immune defense, and a number of other essential functions. Blood levels of selenium decrease drastically during an infection, which is because the organs and cells of the immune system consume large amounts of the nutrient. The thymus, spleen, and lymph nodes contain large quantities of selenium, and selenium supports the production and activity of T cells and other white blood cells. The thymus decrease in size, as you grow older and studies conducted with chickens show that low dietary selenium causes it to shrink even faster at the same time as impairing the activity of T cells in the blood.

Are you getting enough selenium?

The agricultural soil in Europe is generally low in selenium, and for that reason, crops are low in the nutrient, as well. The average selenium intake in Denmark (and many other European countries) is below the recommended daily intake level and way below the selenium intake in countries like the US and Japan. When supplementing, it is generally best to choose selenium yeast with a variety of different selenium species, as this resembles the natural blend of selenium compounds that you get from eating a balanced diet.

Did you know that the soil is leached from the farmland, which is why farmers for decades have added selenium to the animal feed to prevent a number of different deficiency diseases?

Zinc counteracts infections, but many people lack the nutrient

Zinc is necessary for more than 300 different enzyme reactions that help regulate the immune defense, thyroid function, nervous system, and a number of other vital functions. Unfortunately, zinc deficiencies are quite common. Sugar, birth controls, inorganic iron supplements, and ageing processes can interfere with the body’s zinc uptake, and it can be difficult to get enough zinc from vegetarian and vegan diets. Getting too little zinc can affect your immune system, but it can also disturb the numerous enzyme processes, of which zinc is a part.

Zinc sources and official recommendations

Zinc is mainly found in meat, shellfish, dairy products, nuts, kernels, and beans. The body absorbs animal sources better than plant sources. The average zinc intake (in Denmark) is less than the recommended intake (RI) level, which is currently about 10 mg. Many older people have difficulty with absorbing zinc and may therefore become deficient, even if they get enough of the nutrient from their food or from supplements.

It is inexpensive to measure zinc levels in plasma

The typical treatment for diagnosed zinc deficiency is zinc supplementation, depending on the severity of the deficiency and the patient’s diet. When treating a zinc deficiency, it is important to continue taking zinc even after the zinc concentration in blood is normalized, which is because most of the zinc in the body is not found in our blood but in different tissues.

Iron deficiencies are also common

We need iron for blood formation, for our color, and for our immune defense. Lack of iron may be a result of anemia, unhealthy eating habits, lack of gastric juice, too much calcium from dairy products and supplements, and from using antacids, aspirin, tetracycline, and NSAID preparations. It is a good idea to have someone measure your iron status, if you suspect that you lack iron. Only take an iron supplement if your doctor recommends it, because iron also catalyzes free radicals and should therefore only be ingested in the exact right quantities. Vitamin C and an adequate amount of gastric juice in the stomach helps the uptake of iron in the body.

Ageing processes impair the immune system, while antioxidants counteract the damage

Scientists from The Scripps Research Institute in Florida have shown that even premature ageing processes can harm central parts of the immune defense, making us more vulnerable to infections. At the same time, studies have shown that supplementing with vitamins C and D plus selenium and zinc can compensate for this.


Jonathan Grau Møller. Bakterier i blodet: Tusindvis af patienter får en infektion, mens de er indlagte. Nyheder/Regionale/Fyn 12. sep. 2018

Jens Kondrup. Underernæring. Det skjulte samfundsproblem Kost- og ernæringsforbundet. 2014

Romy Conzade et al. Prevalence and Predictors of Subclinical Micronutrient Deficiency in German Older Adults: Results from the Population-Based KORA-Age Study. Nutrients 2017

University of Copenhagen. Vitamin D crucial to activating immune Defences. 2010

James Mcintosh: Age-related immune system decline slowed by antioxidants. Medical News Today 2015

Scripps Research Institute. Study shows how aging cripples the immune system, suggesting benefits of antioxidants. Science Daily. 2015

X Peng et al. Low dietary selenium induce increased apoptotic thymic cells and alter peripheral blood T cell subsets in chicken. Biol Trace 2011

Danmarks Fødevare forskning: Selen og sundhed

Ananda S Prasad. Zink in Human Health: Effect of Zink on Immune Cells. Molecular Medicine 2008

Pernille Lund. Immunforsvarets nye ABC. Hovedland. 2012

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