What is perimenopause: symptoms, timeline and what helps

Almost everyone has heard of menopause, but the term perimenopause unfortunately remains largely unknown to many women — even though it is during this period that they experience significant physical and hormonal changes. If you have the feeling that your body has been behaving differently lately, you may have entered the transitional phase that biologically precedes menopause itself.

In this article, we explain what actually happens in the body during perimenopause, why weight and metabolism change, and how the right nutrition and targeted supplementation can help you manage this period successfully.

Article at a glance

1. Perimenopause vs. menopause: what is the difference?
2. What are the most common symptoms of perimenopause?
3. Metabolic changes in perimenopause: why weight and body shape change
4. Bone health in perimenopause: why it is at risk and how to protect it
5. Sleep in perimenopause
6. Four reasons to commit to strength training
7. How to support your body through nutrition
8. Supplements in perimenopause: what actually helps
9. Key Takeaways

Perimenopause vs. menopause: what is the difference?

Many people use these two terms interchangeably, but from a medical perspective, they describe two distinct phases.

Perimenopause refers to the period during which the ovaries gradually reduce their production of hormones — primarily oestrogen and progesterone. The average age of onset is 40–44, though in some women it can begin as early as the late 30s. On average, perimenopause lasts 4 to 8 years. During this time, hormone levels fluctuate unpredictably — like a rollercoaster — which is what causes most of the typical symptoms. Pregnancy is still possible during perimenopause, because ovulation can continue even with irregular cycles.

Menopause is in fact a single specific moment in time. It is diagnosed retrospectively, at the point when a woman has had no menstrual period for 12 consecutive months. Everything that follows is called post-menopause.

What are the most common symptoms of perimenopause?

Perimenopause symptoms, caused by hormonal fluctuation, vary considerably between women. Some experience minimal disruption; for others, the changes significantly affect everyday life.

The most commonly reported symptoms include:[1]

• Irregular periods — cycles may become shorter, longer, heavier, or lighter (typically the luteal phase shortens and menstrual bleeding becomes heavier)

• Hot flushes and night sweats — the classic manifestation of oestrogen fluctuation, which affects the thermoregulatory centre in the brain

• Sleep disturbances — difficulty falling or staying asleep, often linked to night sweats or elevated cortisol

• Mood changes — irritability, low mood, or anxiety, particularly in the premenstrual phase. Progesterone has calming properties; as its levels fall, women can become more prone to irritability and anxiety.

• Brain fog — difficulty concentrating or recalling information

• Fatigue — even with adequate sleep

• Joint pain and muscle tension

• Changes in libido

• Vaginal dryness or bladder sensitivity

• Dryness of mucous membranes

• Increased histamine sensitivity — which can trigger skin reactions, headaches, or digestive symptoms

Metabolic changes in perimenopause: why weight and body shape change

Many women at this stage find that they are gaining weight even though they eat and exercise the same as before. This is not a failure of willpower — it is a biological process driven by hormonal changes. Research points to the following mechanisms:[2]

1. Fat redistribution due to oestrogen

Declining oestrogen changes the way the body stores fat. Whereas during the reproductive years fat tends to accumulate on the hips and thighs, during perimenopause it increasingly deposits around the abdomen. This is known as visceral (intra-abdominal) fat, which is metabolically active and raises the risk of cardiovascular disease.

2. Loss of muscle mass (sarcopenia)

With age and declining hormones, we naturally lose muscle mass. Because muscle consumes more energy than fat, this loss slows the basal metabolic rate — the body burns fewer calories at rest.[3]

3. Insulin resistance

One of oestrogen's functions is to increase cellular sensitivity to insulin — in other words, the body's ability to respond to insulin effectively and process blood sugar. As oestrogen declines, insulin receptors on cell surfaces become less responsive to insulin signals, and insulin resistance develops. The body then processes carbohydrates less efficiently, leading to stronger cravings for sugar and easier accumulation of energy as fat.[2]

4. Cardiovascular health and cholesterol

Oestrogen has a protective effect on cardiovascular function. In many women, cholesterol levels begin to rise during perimenopause even though diet and physical activity have not changed significantly. LDL cholesterol tends to increase, HDL may fall, and triglyceride (TAG) levels rise. LDL remains in circulation longer, its concentration increases, and the risk of oxidation and deposition in vessel walls increases.[4]

Bone health in perimenopause: why it is at risk and how to protect it

Oestrogen plays a key role in protecting bone mass. Once its levels begin to fall, the process of bone resorption starts to outpace bone formation. This significantly raises the risk of bone thinning (osteoporosis) and fractures, with the greatest losses in bone density occurring in the first years after menopause. Nutrition focused on calcium, vitamin D3, and K2, combined with strength training, has the greatest preventive impact during this period.[5]

Sleep in perimenopause

Sleep quality is one of the fundamental pillars of health during perimenopause. During the night, the body regulates cortisol — the stress hormone — and elevated cortisol levels directly inhibit fat breakdown and deepen insulin resistance. Without sufficient deep sleep, the body cannot regenerate effectively. Every other manifestation of perimenopause becomes significantly harder to manage in the presence of chronic sleep deprivation.

Four reasons to commit to strength training

Regular strength training is one of the most effective tools for protecting health and maintaining body weight during perimenopause.

• Supporting bone health: resistance (strength) training demonstrably stimulates osteoblasts — the bone cells that build new bone tissue — and supports increased bone density.

• Improving insulin sensitivity: muscle activity supports glucose transport into muscle cells independently of insulin. Muscles act as a "sugar sponge" and after exercise can absorb sugar from the bloodstream entirely on their own, without requiring insulin signalling.[6]

• Preventing sarcopenia and boosting metabolism: strength training slows the natural loss of muscle and can continue to build muscle mass. More muscle means the body burns more energy — even while at rest or asleep.

• Better mood and sleep: regular exercise supports serotonin production and lowers cortisol levels, which has a positive effect on sleep quality and psychological well-being.

Investing in muscle mass is one of the best things you can do for your health — it supports independence and vitality for many years ahead. Consistency, correct technique, and progressive increases in load are the key principles.

You can read more about strength training in the article: "Strength Training for Women: Benefits for Hormones, Metabolism & Health".

How to support your body through nutrition

The right dietary adjustments can significantly reduce perimenopause symptoms and stabilise body weight. The goal is not calorie restriction, but rather minimising blood sugar fluctuations and ensuring adequate nutrient intake for metabolic processes.

• Increasing protein intake: adequate protein intake prevents sarcopenia, helps maintain a longer feeling of fullness, and stabilises blood sugar. For a woman without regular strength training, the recommendation is 1.0–1.2 g per kg of body weight per day; for an actively exercising woman, 1.4–1.8 g/kg/day.[3]

• Reducing simple carbohydrates and ultra-processed foods: sugars found in industrially processed foods, fruit juices, smoothies, and alcohol are absorbed rapidly. In the context of reduced insulin sensitivity, they directly stimulate lipogenesis (fat storage) in the visceral area.

• Using fibre: soluble fibre (e.g., legumes, oats, flaxseed, vegetables) slows the absorption of carbohydrates and ensures a gradual release of glucose into the bloodstream, thereby lowering the glycaemic index of the diet.

• Including phytoestrogens: these are plant compounds that can bind to oestrogen receptors in the body and gently compensate for the deficiency of endogenous oestrogen. Research suggests that regular consumption of soya (tofu, tempeh, edamame) and flaxseed may reduce the intensity of hot flushes.[7]

Supplements in perimenopause: what actually helps

During perimenopause, hormonal fluctuation triggers systemic changes that affect the nervous system, cardiovascular health, bone metabolism, and insulin sensitivity. Well-chosen supplementation can reduce the negative impact of these changes.

• Magnesium: supports sleep quality, muscle relaxation, cortisol regulation, and helps cells process sugar more effectively, thereby contributing to the reduction of insulin resistance.[8] The magnesium bisglycinate form is ideal to take at night for its calming effect and to support better sleep.

• Vitamin B6: together with magnesium, it forms a synergistic pair in the body. Vitamin B6 is essential for the production of serotonin and GABA — neurotransmitters that support emotional stability, calm, and sleep. The combination of magnesium and vitamin B6 may help restore emotional balance and support normal hormonal activity.

• Omega-3 fatty acids (EPA and DHA): these polyunsaturated fats help regulate inflammatory processes in the body and support cardiovascular health.[4] Omega-3 also helps cells retain moisture, which is relevant for dry skin and mucous membranes caused by declining oestrogen.

• Vitamin D3 + K2: this combination is essential for maintaining bone density during the period of accelerated bone resorption. Vitamin D3 supports calcium absorption, while vitamin K2 directs calcium into the bones and prevents it from depositing in soft tissue and blood vessels.[5]

• Iron: heavy or irregular periods can deplete iron stores. Fatigue in perimenopause is not always hormonal — in cases of heavy bleeding, it is advisable to check ferritin levels in the blood and, where a deficit is confirmed, to consider supplementation.

• Zinc: supports immune function and skin integrity, both of which can be affected by hormonal changes.

Key Takeaways

Sources:

1. Santoro N et al. Perimenopause: From Research to Practice. Journal of Women's Health. 2016;25(4):332–339. doi:10.1089/jwh.2015.5556

2. Carr MC. The Emergence of the Metabolic Syndrome with Menopause. Journal of Clinical Endocrinology & Metabolism. 2003;88(6):2404–2411.

3. Bauer J et al. Evidence-Based Recommendations for Optimal Dietary Protein Intake in Older People. Journal of the American Medical Directors Association. 2013;14(8):542–559.

4. Mozaffarian D et al. Omega-3 Fatty Acids and Cardiovascular Disease. Journal of the American College of Cardiology. 2011;58(20):2047–2067.

5. Cashman KD. Vitamin D and Osteoporosis Prevention. Journal of Steroid Biochemistry and Molecular Biology. 2007;103(3–5):392–394.

6. Richter EA, Hargreaves M. Exercise, GLUT4, and Skeletal Muscle Glucose Uptake. Physiological Reviews. 2013;93(3):993–1017.

7. Lethaby A et al. Phytoestrogens for Menopausal Vasomotor Symptoms. Cochrane Database of Systematic Reviews. 2007;(4):CD001395.

8. Barbagallo M, Dominguez LJ. Magnesium and Type 2 Diabetes. World Journal of Diabetes. 2015;6(10):1152–1157.