Magnesium After Summer: Why You Need It and How to Choose the Right Form

Fatigue that does not disappear even after resting, night-time leg cramps, poor sleep and irritability without an obvious reason – a familiar picture in autumn. One common but underestimated culprit is magnesium deficiency. During summer, the body loses this mineral more intensively than usual: through sweating in hot weather and during training, an unbalanced holiday diet and increased stress when returning to a working routine. By September, many people's magnesium stores are noticeably below normal – and this directly affects how they feel, their sleep quality and recovery after physical activity.

Why Do You Need Magnesium? Key Functions

Magnesium is involved in more than 300 biochemical reactions in the body. It is one of the busiest minerals – without it, muscles, the nervous system and energy metabolism cannot function normally.

Muscles and cramps. Magnesium is responsible for relaxing muscle fibres after contraction. A deficiency is one of the most common causes of night-time leg cramps, muscle twitching and the feeling that your body cannot relax even after a workout.

Nervous system. Magnesium reduces nervous system excitability: when levels are adequate, people respond more calmly to stress, find it easier to switch between activities and fall asleep more quickly. With a deficiency, increased anxiety, irritability and difficulty relaxing become familiar everyday problems.

Energy metabolism. Magnesium is essential for the synthesis of ATP, the molecule the body uses as fuel for all activity. Without sufficient magnesium, cells produce less energy, and tiredness becomes a constant rather than a temporary condition.

Sleep and recovery. Magnesium is involved in melatonin production and lowers levels of cortisol, the stress hormone that prevents proper relaxation at night. People with normal magnesium levels generally fall asleep faster and wake up feeling more rested.

Why Is Magnesium Deficiency More Common After Summer?

Summer creates several conditions in which magnesium stores decrease more quickly than usual.

Through sweating, the body loses not only water but also electrolytes, including magnesium. The more active your summer is, with workouts, beach holidays and walks in hot weather, the greater the total loss of the mineral.

On holiday, diets often become less balanced. Nuts, pulses, dark leafy greens, buckwheat and seeds – the main dietary sources of magnesium – take a back seat to lighter, irregular meals. Magnesium is still present in food, but not in the amounts the body is accustomed to.

Returning to work in September is stressful in itself. Stress both increases the body's need for magnesium and impairs its absorption. Caffeine and alcohol, which are often consumed more frequently than usual during summer, also accelerate magnesium excretion through the kidneys.

It is the combination of these factors that explains why so many people complain about tiredness, poor sleep and cramps in autumn – and why magnesium supplements become particularly relevant at this time of year.

Magnesium in Food: Is Diet Alone Enough?

The main dietary sources of magnesium include pumpkin and sunflower seeds, almonds and cashews, black beans and chickpeas, buckwheat and oats, spinach and other dark leafy greens, and dark chocolate with a high cocoa content.

In theory, you can obtain your daily requirement from these foods. In practice, however, the amount of magnesium that actually reaches the cells often falls below the recommended level: heat treatment reduces its content in food, while chronic stress, caffeine and certain medicines interfere with absorption. Magnesium supplements are not a replacement for a healthy diet, but they are a practical and convenient way to address a deficiency, particularly when eating habits are irregular.

Forms of Magnesium: What Is on the Label and Which Should You Choose?

When you look at a magnesium supplement on the shelf, you will always see more than just the word “magnesium” – it will be a specific salt or chelate. The form determines bioavailability, meaning how well the mineral is absorbed by the body.

Magnesium citrate. A salt of magnesium and citric acid. One of the best-studied forms with good bioavailability: it dissolves well and is absorbed quickly. A versatile option for daily use, muscle support and recovery after training. At high doses, it may have a mild laxative effect.

Magnesium glycinate (bisglycinate). Magnesium bound to the amino acid glycine. It is well tolerated by the stomach and has virtually no laxative effect. Glycine itself has calming properties, which makes this form particularly suitable for sleep and reducing anxiety. One of the best options for long-term daily supplementation.

Magnesium malate. A salt of magnesium and malic acid. Malic acid is involved in the Krebs cycle, the process of cellular energy production. This is why malate is primarily recommended for chronic fatigue and intense training, when supporting energy metabolism is important.

Magnesium oxide. The cheapest and most widely available form. It contains a high amount of magnesium per tablet, but its bioavailability is low: the body absorbs only a small proportion. It works well as a mild laxative but is less effective than other forms for correcting a deficiency.

Practical summary: for most people, citrate or glycinate will be the best choice. If your focus is on sleep and the nervous system, choose glycinate. For supporting energy and recovery after intense exercise, choose malate. Magnesium oxide is best avoided as your main magnesium supplement.

Magnesium + B6: Why Does This Combination Work?

You will often see “magnesium + B6” on supplement packaging – and this is not simply a marketing trick. Vitamin B6 (pyridoxine) increases magnesium bioavailability: it helps the mineral to be absorbed more effectively in the intestines and remain inside cells. In addition, B6 itself is important for normal nervous system function and the synthesis of neurotransmitters – substances that regulate mood and responses to stress.

A magnesium + B6 complex is particularly appropriate when stress, anxiety, sleep problems and returning to training after a break are the main concerns. It addresses several needs with a single supplement, which is convenient if you do not want to take several separate products.

When and How Should You Take Magnesium?

The most convenient time to take magnesium is in the evening: it helps relax muscles and reduce nervous system excitability before bedtime. After a workout is also a good time for recovery if you train in the evening. It is better to take magnesium with food and a glass of plain water – calcium (for example, in milk) competes with magnesium for absorption.

A standard supplement dosage is 200–400 mg of elemental magnesium per day. It is best to start at the lower end and monitor how your body responds. The first changes – better sleep, reduced irritability and fewer cramps – usually become noticeable after 2–4 weeks of regular use. Magnesium does not work immediately, but a consistent approach produces lasting results.

At SportFit.ee, the Vitamins and Minerals category offers a wide range of magnesium supplements in different forms – citrate, glycinate and malate – as well as magnesium complexes with vitamin B6 for those looking to address several autumn concerns at once. When choosing a product, pay attention to the magnesium form and the amount of elemental magnesium per serving – these are the parameters that determine the supplement's actual benefits.

Frequently Asked Questions

Can You Take Magnesium Every Day?

Yes, magnesium is taken daily in courses, usually lasting 1–3 months. This is the standard approach: with regular supplementation, magnesium levels in the tissues gradually return to normal. After a course, you can take a break or continue if necessary.

Which Form of Magnesium Is Best Absorbed?

Glycinate (bisglycinate) and citrate are considered the forms with the best bioavailability. Magnesium oxide is significantly less well absorbed, although it is widely available because of its low price.

Why Do My Legs Cramp at Night, and How Is This Related to Magnesium?

Night-time cramps are one of the classic signs of magnesium deficiency. This mineral is involved in relaxing muscle fibres after contraction; when levels are low, muscles have greater difficulty relaxing. Taking magnesium regularly before bedtime often solves this problem within 1–2 weeks.

Do You Need B6 in the Formula, or Is Magnesium Alone Enough?

Both options work. B6 improves magnesium absorption and supports the nervous system, which is especially relevant during stress and sleep disturbances. Pure citrate or malate without B6 also works well for muscle recovery and supporting energy metabolism.

Can Magnesium Be Taken with Other Sports Supplements?

Yes. Magnesium combines well with protein, BCAA, electrolytes and omega-3 – they serve different purposes and do not compete with one another. It is better to take calcium at a different time of day, as high doses of these minerals taken together can slightly reduce each other's absorption.

How Can You Tell If You Are Not Getting Enough Magnesium?

Chronic fatigue, unexplained anxiety, sleep problems, frequent cramps and muscle twitching, and increased irritability are all typical signs. A blood test provides a definitive answer, but if several symptoms occur together – particularly after an active and stressful summer – magnesium should be one of the first things to consider.