How seasonal transitions affect our hormonal balance and health
With the arrival of spring, our bodies gradually awaken from a period of relative hibernation. These seasonal changes are not simply a transformation of our environment – they also trigger significant biological adaptations within our bodies. Let's examine how our bodies react to the transition from winter to spring, and vice versa.
🌞 Spring: a physiological awakening
Light: our natural hormonal regulator
With longer days, our exposure to natural light increases considerably. This increased brightness has a direct effect on our pineal gland, which reduces its production of melatonin (the sleep hormone). At the same time, our brain stimulates the production of serotonin, often called the "happiness hormone."
Quiz: Did you know that...?
How much daily exposure to natural light is recommended in spring to maintain good hormonal balance?
a) 5-10 minutes
b) 15-30 minutes
c) 1-2 hours
(Answer: b - 15-30 minutes is enough to trigger vitamin D production and regulate your circadian rhythm)
Vitamin D: the "sunshine nutrient"
In spring, our skin begins to efficiently synthesize vitamin D again thanks to UVB rays. After the winter months when our reserves are depleted, this regeneration is crucial for:
- Strengthening our immune system
- Improved calcium absorption
- Regulating our mood
Sex hormones are awakened
Spring is often accompanied by a slight increase in sex hormones, particularly testosterone in men and estrogen in women. This phenomenon partly explains why spring is traditionally associated with the mating season in the animal kingdom.
This cycle has a certain innate logic, occurring before winter and again at the beginning of spring. It's as if the body is preparing itself for high/low temperatures and levels of exposure. But what's even more interesting is that the effect is the same even though the situations are opposite, demonstrating the body's resilience and adaptive nature.
The same phenomenon can be observed every day, the lowest level being deep sleep but followed by an explosion, which transforms the end of our night and our awakening to an excess of testosterone and followed by a stable decrease.
Testosterone plays a central role in the human hormonal network, influencing various receptors beyond the reproductive system. In men, where concentrations are naturally 10 to 20 times higher, it amplifies muscle and bone density via androgen receptors present in these tissues.
In women, although present in smaller quantities, it remains essential for libido and overall energy, interacting subtly with estrogen. This hormone follows not only seasonal but also remarkable circadian cycles.
This "morning burst" of testosterone prepares the body for daytime activity before gradually decreasing throughout the day – a cycle which, like seasonal variations, testifies to the meticulous orchestration of our biology according to natural rhythms.
❄️ Winter: Adaptation and Conservation
Metabolic slowdown
When autumn gives way to winter, our bodies begin a reverse transition. The decrease in sunlight triggers a series of physiological adaptations:
- Increase in melatonin
- Decreased serotonin (which may contribute to seasonal affective disorder)
- Subtle modification of metabolism to conserve energy
Vitamin D deficiency
In winter, in temperate and northern regions, the skin's synthesis of vitamin D becomes virtually impossible. According to the French National Institute of Health and Medical Research (INSERM), more than 80% of French people have insufficient vitamin D levels at the end of winter.
🔄 How to adapt harmoniously to seasonal changes?
Your seasonal transition checklist:
Gradually adapt your sleep schedule to the variations in light.
Expose yourself to natural light first thing in the morning (15-30 minutes)
In winter, consider vitamin D supplementation (consult your doctor).
Adjust your diet to seasonal produce
Maintain regular physical activity, ideally outdoors
Seasonal diet and hormonal balance
In spring, prioritize:
- Leafy green vegetables (spinach, arugula)
- Fresh fruits are rich in antioxidants.
- Lean proteins
In winter, opt for:
- Root vegetables rich in fiber
- Fermented foods to support your gut microbiota
- Natural sources of vitamin D (oily fish, eggs)
To go further
Have you noticed any significant changes in your energy or mood during seasonal transitions?
For a personalized assessment of your seasonal hormonal balance, consult a healthcare professional who can offer recommendations tailored to your specific profile. For example, vitamin D supplementation is recommended in winter but depends on your age and where you live on this beautiful planet . 🌍🌱
The Science Behind Seasonal Cravings
Kräuchi and Wirz-Justice's research has revealed a fascinating phenomenon: humans consume approximately 200 extra calories per day during autumn and winter, with a marked preference for high-fat foods. This evolutionary adaptation fits perfectly within our understanding of seasonal hormonal changes.
Just as melatonin levels rise and vitamin D levels fall during the darker months, our bodies also adjust their hunger and satiety signals. The decrease in natural light alters the production of leptin and ghrelin, prompting us to store energy reserves.
This mechanism, once essential to our survival, works in tandem with the winter metabolic slowdown we described earlier. This remarkable synchronization between our external environment and our internal biology underscores the importance of understanding and adapting our eating habits to the natural rhythms of the seasons to maintain optimal balance. 🐻
