On the Trail of Nutrient Thieves—Where They Hide and How We Can Outwit Them

In our hectic daily lives, it can sometimes be a challenge to provide our bodies with all the essential nutrients they need. An unbalanced diet, alcohol, smoking, medications, and stress can lead to nutrient deficiencies. In this article, learn what nutrient thieves are, where they hide, and how we can outsmart them.

What Are Nutrients?

Nutrition plays a crucial role in our health and well-being. It supplies our bodies with essential nutrients that are indispensable for the proper functioning of many bodily processes. Nutrients can be divided into macronutrients and micronutrients. Macronutrients primarily provide the body with energy. These include proteins, carbohydrates, and fats. Micronutrients do not provide energy but are indispensable for maintaining vital functions. They are what are known as essential nutrients. This means that the body cannot produce them on its own and must obtain them from food. Micronutrients include vitamins such as folic acid, vitamin C, and vitamin D, as well as minerals such as calcium, zinc, and iron.¹

What are vital substances?

Vital substances refer to the micronutrients mentioned above (vitamins and minerals). But they also include other substances that have positive effects on health, such as phytochemicals2.

Foods That Steal Nutrients

Some foods and food ingredients can hinder the absorption of nutrients from the intestines. Because the body lacks these nutrients, they are called nutrient robbers. Typical nutrient robbers in our diet include coffee, black tea, oxalic acid, and phytic acid.

Coffee and Black Tea

Coffee and black tea contain tannins. When consumed with meals, they can hinder the absorption of zinc³^{, ⁴}, calcium, and iron from plant-based foods, potentially leading to deficiencies⁵^{, 6}. Iron is an essential component of hemoglobin and plays a vital role in our body’s oxygen transport. While calcium is primarily important for bones and teeth⁷, we need zinc for a properly functioning immune system⁸.

The caffeine found in coffee and black tea also contributes to increased excretion of calcium⁹^,¹⁰ and magnesium in the urine¹¹. Magnesium supports muscle function and the nervous system and is ^involved in energy production in the body^¹¹.

Sugar and Sweets

For a long time, it was believed that sugar was a “nutrient thief” because the body needs vitamin B1 to break it down. However, scientific studies have shown that the vitamin is not consumed in this process but ^can be reused by the body repeatedly12. However, high consumption of sugar-rich foods can indirectly contribute to nutrient deficiencies. Since sugar and sugary foods typically contain many calories but almost no nutrients, they provide the body with almost exclusively so-called “empty calories.” If you eat large amounts of nutrient-poor, sugary foods, you simply lose your appetite for more nutrient-rich foods. The result is an unbalanced diet with a lower intake of important micronutrients.

Food Components

A nutrient-depleting substance that many have probably never heard of is found primarily in spinach, rhubarb, Swiss chard, beets, nuts, cocoa, and black tea. We’re talking about oxalic acid. In the gut, oxalic acid forms insoluble compounds with calcium, magnesium, and iron from food. As a result, the body has difficulty absorbing these nutrients. This can lead to mineral deficiencies in people with an unbalanced diet, vegans, and others who do not consume calcium-rich milk and dairy products. With a balanced diet, however, the occasional consumption of foods containing oxalic acid is harmless. The oxalic acid content can also be ^reduced through cooking.¹³

Phytic acid is another plant compound that can impair nutrient absorption. Phytic acid is found primarily in whole grains, legumes, and nuts. It serves as a storage form of phosphate for plants, which the seedling needs for growth. However, phytic acid forms insoluble compounds with magnesium, calcium, zinc, and iron, thereby hindering their absorption by the body. Soaking, sprouting, and fermenting can, however, reduce the phytic acid content14.

Nutrient Thieves: Alcohol, Smoking, and Stress

An unhealthy lifestyle involving regular alcohol consumption, smoking, and stress is also considered a nutrient robber and can lead to nutrient deficiencies.

Alcohol

Excessive alcohol consumption has a negative impact on the body’s supply of essential nutrients. Alcohol impairs the absorption and storage of folic acid and vitamins B1, B2, and ^B6¹⁵. Alcohol also disrupts the conversion of vitamins—particularly the B vitamins, as well as vitamins A, D, and E—into their metabolically active forms.¹⁶ In addition, the body lacks vitamin C and selenium because alcohol ^reduces their absorption from the intestines.¹⁵ Alcohol also increases the excretion of magnesium and zinc through the kidneys¹⁵^{, ¹¹}. This results in reduced absorption and increased excretion of important nutrients. At the same time, the body’s need for certain micronutrients increases, which contributes to nutrient deficiencies.

Smoking

Smoking not only harms health but also affects nutrient supply. When smoking, harmful free radicals enter the body. To protect itself from these, the body requires increased amounts of antioxidants such as vitamin C, which can protect cells from damage caused by free radicals. For this reason, smokers have a need for vitamin C that is up to 40% higher than that of nonsmokers.¹⁷ In addition, smoking reduces the amounts of calcium¹⁸ and vitamin ^D¹⁹ available in the body—important nutrients for our bone metabolism.

Stress

Stress, whether in daily life or at work, is omnipresent in today’s hectic world. However, chronic stress in the form of prolonged physical, mental, or emotional strain can negatively impact the body’s supply of micronutrients. Studies show that stress reduces the concentration of magnesium, zinc, calcium, iron, and niacin in the body, which ^can lead to nutrient deficiencies^.²⁰

Medications as Nutrient Thieves

Certain medications can also interfere with nutrient absorption and, especially with long-term use, lead to nutrient deficiencies. These medications include antibiotics, birth control pills, blood pressure medications, cholesterol-lowering drugs, diabetes medications, diuretics, and acid-blocking medications. Some of these medications inhibit the absorption of micronutrients from the intestines. Others, in turn, lead to increased excretion in the urine or interfere with nutrient metabolism. Depending on the medication, this can affect vitamins B6, B12, folic acid, vitamin C, vitamin D, vitamin E, iron, calcium, magnesium, and zinc.²¹

How can an optimal nutrient intake be ensured despite these nutrient-depleting factors?

First and foremost, nutrient needs should be met through a balanced diet. If this is not possible—for example, in certain life situations—and nutrient robbers such as stress, medication use, or smoking contribute to an insufficient nutrient supply, dietary supplements can play a valuable role in ensuring an optimal supply of essential nutrients.

How can you outsmart nutrient-depleting factors?

• Don’t drink coffee or black tea immediately after a meal; wait at least 30 minutes—or better yet, 2 hours—after eating. This allows zinc, calcium, and iron from plant-based foods to be optimally absorbed by the intestines despite the tannins they contain.
• Have a glass of orange juice with your muesli in the morning instead of coffee or black tea. This way, iron absorption isn’t disrupted by tannins; in fact, it’s actually enhanced by the vitamin C in the juice.
• Instead of snacks that are high in sugar, opt for a healthy, nutrient-rich apple or vegetable sticks.
• Cook foods containing oxalic acid—such as spinach, Swiss chard, and beets—before eating them; this allows some of the oxalic acid to leach into the cooking water (discard the cooking water).
• Maintain a healthy lifestyle: Reducing stress, drinking alcohol in moderation, and avoiding smoking all contribute to a better supply of essential nutrients.
• In certain life situations where a balanced diet is difficult to maintain, you may want to consider taking dietary supplements.

Sources

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