CARENCE Persistent fatigue: 5 signs of a nutritional deficiency you shouldn’t ignore

You get enough sleep, manage your stress, and yet the fatigue is still there - persistent, unexplained, sometimes accompanied by low mood or poor concentration. Before attributing it solely to your lifestyle, it is worth looking at your diet. When certain micronutrients are lacking, they can directly compromise your energy levels. Here are 5 signs that deserve your attention.

1. You wake up tired despite a full night's sleep

A 7- to 8-hour night should be enough to recover. If it is not, your body may be lacking iron or B vitamins. Iron is essential for transporting oxygen in the blood: even a slight deficiency reduces oxygenation in the muscles and brain, causing fatigue from the moment you wake up. Vitamins B1, B2, B3, and B5 are involved in cellular energy production; without them, your cells struggle to convert nutrients into usable fuel.

Women of childbearing age, vegetarians, and people following restrictive diets are particularly at risk of iron deficiency. A blood test can confirm the deficiency.

2. You experience mental fatigue and difficulty concentrating

Brain fog, slow thinking, and difficulty staying focused - these symptoms often point to a lack of magnesium or vitamin B6. Magnesium is involved in more than 300 enzymatic reactions, including the synthesis of ATP (the body's energy molecule). Vitamin B6 supports protein metabolism and the production of neurotransmitters such as dopamine and serotonin, which are essential for mental clarity.

Chronic stress worsens magnesium deficiency because cortisol promotes its elimination through the urine. The result: the more stressed you are, the more you lose - and the more fatigue sets in.

3. Your mood fluctuates for no apparent reason

Mood swings, irritability, or a tendency to feel discouraged may signal a lack of vitamin D3, zinc, or folate (B9). Vitamin D plays a role in serotonin regulation; a deficiency - very common in our latitudes between October and April - is often correlated with low energy and a gloomy mood. Zinc, meanwhile, is essential for neurotransmitter activity and the stress response.

Vitamin B9 (folate) is involved in methylation, a key process in managing oxidative stress and synthesizing the amino acids that are precursors to a positive mood. A mild but lasting deficiency may be enough to disrupt emotional balance.

4. You often get sick or recover slowly

The immune system requires plenty of micronutrients. An organism deficient in vitamin C, zinc, or selenium has weakened natural defenses - and the fatigue associated with repeated infections accumulates. Vitamin C is also a cofactor in collagen synthesis and improves the absorption of non-heme iron (the kind found in plants), thereby doubling its effect on vitality.

Selenium, a mineral that is often overlooked, acts as an antioxidant and supports thyroid function. A slowing thyroid can cause significant fatigue, sometimes mistaken for a simple slump.

5. You need stimulants to get through the day

If coffee, sugar, or energy drinks have become essential for functioning, that is a warning sign. Relying on external stimulants often reflects adaptive fatigue linked to a chronic lack of cellular energy - a sign of a deficiency in Rhodiola (an adaptogenic plant), spirulina, or B vitamins. Rhodiola rosea, a clinically studied adaptogenic plant, helps the body better manage excessive mental strain without causing dependence or an energy crash.

The Epycure solution: the Multivitamin+ Course

When fatigue has multiple causes, targeted supplementation can make all the difference. Epycure Laboratoire's Multivitamin+ Course was formulated to address all of these deficiencies with clinically dosed active ingredients:

• Rhodiola rosea (Rhodiola) - adaptogenic plant: helps reduce nervous fatigue associated with excessive mental strain
• Bisglycinate iron - contributes to normal oxygen transport in the body and helps reduce fatigue
• Vitamin C - helps reduce fatigue and improves iron absorption
• Marine magnesium - helps maintain normal psychological functions and helps reduce fatigue
• Complete B complex (B1, B2, B3, B5, B6, B9, B12) - supports cellular energy metabolism
• Vitamin D3 - contributes to the maintenance of normal immune function
• Zinc & Selenium - cellular protection and immune support
• Spirulina - a source of protein, iron, and plant-based antioxidants

The formula achieves 81.4% naturalness, is made in France (Plumelin, Brittany, AFNOR HACCP certified), and was developed in our Lab'Epycure laboratory. Results observed among our users: 1 in 2 people feel less overwhelmed after just 30 days, 97% report improved physical and mental fitness, and 97% notice an improved mood (34 people, 3 months).

Dosage: 2 capsules in the morning with breakfast. For ages 18 and over. Timeline of effects: renewed energy from day 15, reduced physical fatigue by day 30, lasting mental well-being by day 90.

What to remember

Persistent fatigue is not inevitable. Before looking solely to your lifestyle for the cause, check your iron, magnesium, B and D vitamin, zinc, and selenium levels. A nutritional assessment or simply changing your supplements can transform your energy levels within a few weeks. The key is to take targeted action with well-dosed active ingredients and high-quality sources.