Dietary supplements and seasonality: the annual supplementation calendar

Why should you tailor your dietary supplements to the rhythms of nature?

As the seasons change, light and temperature fluctuate, affecting certain biological rhythms. Chronobiology shows, in particular, that photoperiod influences the secretion of melatonin, which plays a key role in regulating the sleep-wake cycle (1).

Your dietary intake, physical activity and exposure to sunlight also vary throughout the year, with potential implications for your nutritional status. The most telling example is undoubtedly that of vitamin D, whose blood levels are generally higher at the end of summer and lower at the end of winter (2).

A well-planned supplementation schedule therefore allows you to target the periods when certain needs are most acute, so as to provide your body with the right nutrients at the right time.

Spring: supporting the body’s filtration function and revitalising

The physiological mechanism behind the spring transition

Whilst spring is traditionally associated with ‘detox’ regimes, fortunately your body doesn’t wait until March to eliminate waste: the liver, kidneys, intestines and lungs are constantly at work.

Among these organs, the liver plays a pivotal role: its enzymes transform numerous substances to facilitate their elimination via bile or urine (3). In spring, therefore, the aim is not so much to ‘detoxify’ it, but rather to support its natural functions as we adapt to the changes in diet and lifestyle that follow winter.

This season also coincides with the return of many types of pollen (4). If you are sensitive to pollen, do take a look at our allergy calendar and the main periods of exposure.

Key active ingredients: Chlorella, Vitamin C and Magnesium

Chlorella is a green microalgae that is particularly rich in nutrients. It contains, in particular, protein, iron, chlorophyll and several vitamins. Its ability to bind certain heavy metals has been observed experimentally, notably in vitro (5).

Chlorella features Yaeyama chlorella, produced in a controlled environment in Japan.

Vitamin C supports normal energy metabolism, helps reduce fatigue and protects cells against oxidative stress (6). An excellent choice for regaining vitality as winter draws to a close.

The vitamin C in Liposomal Vitamin C is encapsulated in lipid vesicles, which maximise its absorption by the body.

Magnesium, for its part, is involved in a wide range of enzymatic reactions. It contributes to the normal functioning of the nervous system, normal muscle function and the reduction of tiredness and fatigue (7).

OptiMag combines eight forms of magnesium with excellent bioavailability to provide a daily intake of 360 mg.

As the pollen season approaches, certain natural active ingredients have also been the subject of specific research. This is particularly the case for spirulina and greater butterbur, which have been evaluated in several clinical trials involving people suffering from allergic rhinitis (8–9).

To this end, Aller Fight combines spirulina, greater butterbur, bromelain, astragalus and maritime pine extract, which supports respiratory health.

Summer: oxidative protection and regulation of the circadian rhythm

Protecting cells against increased sun exposure

Sunny days generally mean we spend more time outdoors. However, ultraviolet radiation can promote the formation of reactive oxygen species in exposed tissues (10).

Whilst your body has its own antioxidant defences, your diet also provides various compounds that contribute directly or indirectly to this balance, such as vitamins C and E, certain carotenoids and numerous polyphenols (11).

These include flavonoids, a vast family of plant molecules comprising, in particular, quercetin, anthocyanins and flavanols. To learn more about how they work, read our feature on the latest discoveries regarding flavonoids and ageing.

This nutritional strategy is, of course, no substitute for sun protection measures, namely limiting exposure during the hours of peak intensity, wearing suitable clothing and using sun protection.

Key active ingredients: antioxidants, flavonoids and melatonin

Vitamin E helps protect cells against oxidative stress. Certain carotenoids, such as beta-carotene, lutein and lycopene, have also been studied for their potential ability to enhance nutritional photoprotection (12). Combinations of rosemary and grapefruit polyphenols have also been the subject of research in this field (13).

Solar Prep Formula tanning capsules combine, amongst other ingredients, beta-carotene, lutein, lycopene, vitamin E, zinc and Nutroxsun®, a standardised complex of rosemary and grapefruit extracts.

Summer also affects our relationship with light. Longer days delay the onset of darkness, which is an important signal for the night-time secretion of melatonin. Added to this may be heat, travel and disrupted holiday schedules, all of which can disturb sleep. Occasional melatonin supplementation may therefore be considered to help reduce the time taken to fall asleep (14).

The 1 mg Melatonin tablet takes effect within 30 to 60 minutes of taking it.

Autumn: preparing for reduced daylight and boosting immunity

Autumn marks a significant transition: the days are getting shorter, temperatures are falling and the time spent indoors is increasing. As well as preparing for the reduction in daylight, another aim is to provide your immune system with the nutrients it needs to function properly.

The importance of the gut microbiota in the immune response

The gut does not merely serve to absorb nutrients: it also acts as a key interface with the immune system. The microbiota – the collection of microorganisms inhabiting the digestive tract – is in constant communication with the immune cells present in the mucosa. Its bacteria and their metabolites play a key role in the maturation and regulation of immune responses, as well as in maintaining the intestinal barrier (15).

Short-chain fatty acids — such as butyrate, acetate and propionate — produced during the fermentation of fibre are one of the main channels for this communication (16).

Key active ingredients: probiotics, zinc and adaptogenic extracts

To ‘feed’ the beneficial gut bacteria, a diet rich in plant-based foods and fermentable fibre remains essential. Depending on your needs, probiotics can also complement this approach by enriching your gut flora with ‘friendly’ strains.

Probio Forte combines 5 probiotic strains in a gastro-resistant capsule, providing a total of 8 billion microorganisms per dose.

Zinc plays a role in numerous cellular processes. It contributes to the normal functioning of the immune system and helps protect cells against oxidative stress (17). When taking supplements, opt for a chelated form such as zinc bisglycinate: bound to two glycine molecules, the mineral is particularly well absorbed by the body and has greater bioavailability than some more traditional forms, such as gluconate (18).

Advanced Zinc Bisglycinate Lozenges provide 10 mg of zinc bisglycinate in the form of lozenges.

Autumn can also put your ability to adapt to the test, as you return to a busier routine after the summer holidays. So-called adaptogenic plants, such as rhodiola, which helps protect the body from stress; ginseng, which supports vitality; and astragalus, which helps the body defend itself against external agents, are traditionally used to support the body during periods of increased physical or mental strain (19–21).

Adaptix combines eight adaptogenic extracts, including rhodiola, ashwagandha, ginseng, astragalus and schisandra, in a synergistic formula.

Winter: counteracting the lack of sunlight and supporting energy metabolism

Countering seasonal fatigue with targeted supplementation

Fatigue, respiratory infections, reduced exposure to light: winter puts the body under strain on several fronts. The priority, therefore, is to ensure an adequate intake of micronutrients involved in energy metabolism, muscle function and the reduction of fatigue, such as magnesium or vitamins B and C (22).

Vitamin D also warrants particular attention. It contributes to the normal functioning of the immune system, as well as to the maintenance of normal muscle function and bone health (23). The problem is that its synthesis in the skin depends on UVB rays and decreases significantly when exposure to sunlight is insufficient. ANSES has set the nutritional reference value for the adult population at 15 µg per day (24).

Key active ingredients to prioritise: vitamin D3, omega-3 and spirulina

When taking supplements, opt for vitamin D3 (cholecalciferol), which is generally more effective than D2 at raising and maintaining vitamin D levels (25). As it is fat-soluble, it is best taken in an oil-based form, which aids its solubility and absorption in the digestive tract (26).

Vitamin D3 5000 IU provides 5,000 IU of vitamin D3 per oil-based capsule.

Omega-3 fatty acids EPA and DHA are also beneficial during the winter months, particularly for people experiencing low mood. These fatty acids, and DHA in particular, play an important role in the structure and function of neuronal membranes (27). They are also the subject of extensive research into mood, with particularly interesting results for formulations containing sufficient levels of EPA (28).

Super Omega 3 combines EPA and DHA in a pure and stable formula.

Spirulina is packed with protein, phycocyanin and numerous micronutrients (iron, copper, manganese, B vitamins, etc.) in a small volume (29). It is therefore particularly useful in winter to supplement a diet that is often less varied.

Spirulina is made from spirulina sourced from aquaculture that is rigorously monitored in accordance with exacting standards of quality and purity.

The arrival of winter also brings immunity back to the forefront. Certain plants are particularly suited to this purpose, such as echinacea, traditionally used to support the body’s natural defences (30).

Immunity Booster therefore combines organic echinacea, beta-glucans, vitamin C and zinc in a synergistic formula.

Frequently asked questions about the supplementation schedule

Should you take a break between each seasonal course of treatment?

Not necessarily. The appropriate duration of each course of treatment depends on the nutrient, the dose and your individual circumstances. Some supplements are designed to be taken for a few weeks, whilst others can be continued for longer depending on your needs. Just remember to regularly reassess whether they are still beneficial.

Is it a good idea to combine several active ingredients when the seasons change?

Yes, provided that the combination makes sense and the doses remain appropriate. Combining several active ingredients is actually a sensible strategy, as it allows you to target the same physiological function through complementary pathways.

This is precisely the principle behind synergistic formulas, which combine several nutrients within a single supplement and offer the added practical benefit of convenience. However, if you choose to take several separate supplements, avoid taking the same vitamins or minerals in multiple products so that you can keep track of your total intake.

Dietary supplements are not a substitute for a varied and balanced diet or a healthy lifestyle. If you are unwell, taking medication, or are pregnant or breastfeeding, seek advice from a healthcare professional.