When fatigue is more than just the winter blues: Recognizing and understanding iron deficiency

When the alarm clock becomes your natural enemy in the morning and the couch develops magnetic powers from 5 p.m., we like to blame it on the winter blues. Most of the time, stress and gray weather really are the culprits. But if your body feels like someone has permanently pulled the plug, there may be more to it.

Taking a closer look at your iron levels is then a good idea. Maybe you are freezing for two right now, or you get unusually out of breath even with small errands. Iron deficiency is a master of disguise and likes to hide behind ordinary exhaustion.

Below, you will learn which indispensable tasks iron performs, how to interpret your body’s signals correctly, and how you can easily support your vital nutrient balance through nutrition.

More than just an oxygen taxi: Why your body needs iron

Have you ever wondered what exactly iron does in your body? It is far more than just a mineral listed on the back of a package. Iron is one of the essential trace elements. That means the human body depends on it, but cannot produce it itself [1]. Regular intake through diet is therefore necessary [1].

Iron’s best-known job is in the blood. As a component of hemoglobin in red blood cells, it helps take up oxygen in the lungs and deliver it throughout the body [2]. If this transport is impaired, it can become noticeable, for example, as shortness of breath or palpitations. Such symptoms are often described in medical contexts in connection with iron deficiency anemia [3]. But iron does not work only in the blood. It is involved in many other processes that run in the background every day.

The spark for your energy

Inside your cells are the mitochondria, often described as small power plants. Their job is to generate energy in the form of ATP from nutrients such as fats and carbohydrates [4]. For these conversion processes, specific enzymes are needed, which either contain iron or depend on its availability [5]. If iron status drops, these processes can be affected and your subjective sense of energy can change.

A team player for the immune system and hormones

The immune system also cannot function without iron. This trace element is involved in processes that, among other things, affect the activity of immune cells such as T cells and macrophages [5]. At the same time, iron plays a role in hormone metabolism. This includes the production of thyroid hormones, which are involved in regulating metabolism [5].

Iron is also present in the nervous system. It is needed for the formation of certain messenger substances such as dopamine, which are involved in drive, attention, and motivation [5].

A structural contributor for muscles and outward appearance

Iron is also involved in the formation of collagen fibers types 1 and 3. These structures shape, among other things, skin, connective tissue, and tendons [6]. Iron is also relevant in muscle tissue. There it is a component of myoglobin, a protein that stores oxygen in the muscle and makes it available for physical exertion [5].

An altered iron balance can therefore become noticeable both physically and mentally. In scientific literature, connections between iron status, fatigue, and performance are described [2]. Many of these effects develop gradually and are often only noticed once the balance has already shifted.

How you can recognize an iron deficiency

Iron deficiency rarely announces itself with drums and trumpets. Most of the time, it creeps quietly into your everyday life and disguises itself perfectly as normal exhaustion. As long as your body can still draw on its filled iron stores, many things continue without obvious signs. Only when these reserves dwindle do small changes gradually appear. In the stress of everyday life, these are often not immediately interpreted correctly. Especially in winter, when infections are more common and the diet is often more one-sided, such changes are easier to miss.

Pay attention to these messages from your body:

• Persistent fatigue: You feel drained, and this feeling does not really go away even after breaks or good sleep.
• Shortness of breath: You are out of breath faster than usual. Suddenly stairs become a challenge that you used to handle easily.
• Feeling cold: You often have cold hands or feet, even when others find the temperature pleasant.
• Concentration and mood: It is harder to stay focused. You may also feel inner restlessness or nervousness.
• Skin and hair: A look in the mirror shows noticeably pale or dry skin. Brittle nails, increased hair loss, or cracked corners of the mouth can also be signs.
• Susceptibility to infections: You catch every cold wave and are ill more often than usual.

These signals are, of course, not a diagnosis. They function more like small warning lights on your body’s dashboard. Since other causes can also be behind these symptoms, medical clarification is absolutely sensible. Especially if the complaints become constant companions. Whether an iron deficiency is actually present can be clarified most reliably through a blood test, in which, among other things, the ferritin value is evaluated [2].

How it happens in the first place: Pathways to iron deficiency

Iron deficiency rarely hits overnight. It usually develops gradually and quietly. Often your daily life, your diet, and your current life phase interact. Either your body loses more iron than usual, absorbs too little of it, or simply needs an extra portion right now. This often happens completely unnoticed. And it is by no means a sign that you did something wrong. Rather, your organism is responding to changes that are simply part of life.

The causes are as individual as your everyday life. Among the most common reasons are low intake through food, impaired absorption in the intestine, or increased loss due to bleeding [2]. Special phases such as growth, pregnancy, breastfeeding, or intensive sports also challenge reserves. They naturally come with an increased iron requirement. Especially if you eat vegetarian or vegan, it is worth taking a conscious look at your iron status. Plant-based iron is utilized somewhat differently by the body than animal-based iron [2].

How to replenish your iron stores

The best news right up front: your body is an extremely grateful partner. If it gets what it needs, it is happy to work with you. Once you keep an eye on your iron balance, depleted stores can be replenished step by step. That does not happen overnight and it is not magic, but with a bit of patience, good habits, and smart everyday choices, you will get there.

Your meal plan as a source of strength

Iron is hidden in many foods. However, it does not occur in the same form everywhere. People often distinguish between “team animal” and “team plant.” Your body can absorb iron from animal products somewhat more easily than plant-based iron [2]. But plant power can also fill the stores if you know where the treasures are.

Here you can find especially high amounts of iron:

• Red meat, organ meats, fish, and eggs
• Vegetables such as spinach, chard, fennel, or kale
• Whole grains, oats, millet, or amaranth
• Legumes such as lentils, chickpeas, and beans
• Nuts and seeds, especially pumpkin seeds, sesame, or pistachios

Especially if you eat vegetarian or vegan, taking a conscious look at this list is valuable. Plant-based iron may be a bit more “shy” when it comes to absorption, but these foods also bring plenty of other vital nutrients that are good for your body [2].

The perfect match: How to get more out of it

Sometimes it is not so much what you eat, but how you combine it. In your body’s biochemistry, there are real dream teams and difficult relationships. With small tricks, you can significantly support iron absorption.

• Vitamin C is iron’s best friend. A glass of orange juice with muesli or bell pepper strips with whole-grain bread act like a turbo boost for absorption [2].
• Coffee, black tea, and dairy products are more like bouncers. They can inhibit iron absorption [2]. So it is best to enjoy your espresso or cappuccino with some time gap from your meal.
• Choose fresh and minimally processed foods more often. Your body will thank you.

If you need support from the outside

There are phases in life when an optimized diet alone is hardly enough. If stores are severely depleted, if you are pregnant, or if you have an increased requirement, supplements can be a sensible addition [2]. They can help you compensate deficits in a targeted way.

The key here is patience. Iron stores are like a savings account. They fill slowly and steadily, not instantly. Medical supervision is advisable to find the right dosage and keep track of progress.

Curious? In our magazine you will find more exciting articles, including on the following topics:

• Vitamin B12 – where it is found and how to recognize a deficiency
• Winter kale, vitamin C and iron – your natural supporters for the cold season
• Better oxygen supply in spring thanks to iron and vitamin C as natural boosters
• Iron deficiency and iron deficiency anemia
• The right vitamins for hair loss

FAQ – Frequently asked questions

What is functional iron deficiency?

Functional iron deficiency refers to a situation where iron is present in the body, but is not sufficiently available to the cells [7]. This can occur, for example, with chronic inflammation or certain metabolic processes and can mainly be identified through specific blood markers [8].

Which fruit is especially suitable for iron deficiency?

Fruit is not an iron miracle, but it still plays an important role. Varieties such as oranges, berries, kiwi, or blackcurrants provide a lot of vitamin C. This vitamin helps the body absorb plant-based iron from food more effectively and usefully complements iron-rich meals [2].

How much iron should you consume daily?

How much iron the body needs depends strongly on life stage. Women of childbearing age have higher requirements than men, and during pregnancy and breastfeeding the need increases further [2]. The German Nutrition Society (DGE) provides guideline values that offer good orientation [9].

What side effects can occur when taking iron?

Not everyone tolerates iron supplements equally well. Some people react with gastrointestinal complaints such as a feeling of fullness or constipation [2]. A dark coloration of the stool can also occur, but is usually harmless [10].

Can iron upset your stomach?

Yes, that can happen, especially when taken on an empty stomach [2]. If you are sensitive, you often do better when taking iron with a small meal. Which option fits best varies individually.

What happens if an iron deficiency remains unnoticed?

If iron deficiency is not recognized over a longer period, fatigue can intensify and resilience can continue to decline. In some cases, it can develop into iron deficiency anemia, which can be accompanied by symptoms such as fatigue and shortness of breath [3].

Sources
[1] https://www.ncbi.nlm.nih.gov/NBK540969
[2] https://ods.od.nih.gov/Iron-HealthProfessional
[3] https://www.nhs.uk/iron-deficiency-anaemia
[4] https://pmc.ncbi.nlm.nih.gov/PMC6541229
[5] https://lpi.oregonstate.edu/minerals/iron
[6] https://www.ncbi.nlm.nih.gov/NBK225480
[7] https://pmc.ncbi.nlm.nih.gov/PMC7983022
[8] https://ashpublications.org/Iron-deficiency
[9] https://www.dge.de/referenzwerte/eisen
[10] https://www.webmd.com/iron-vitamin-c-sustained-release-oral