Lifestyle factors are linked to more than a quarter of healthy years lost to breast cancer worldwide, according to the largest study of its kind.

The research analysed data from population-based cancer registries across more than 200 countries between 1990 and 2023 to examine how lifestyle affects the global burden of breast cancer.

The study, published in Lancet Oncology, also used the data to forecast trends in breast cancer cases up to 2050.

It found high red meat consumption had the largest impact, linked to nearly 11 per cent of healthy life lost to the disease.

Tobacco use, including secondhand smoke, accounted for 8 per cent, followed by high blood sugar (6 per cent), high body mass index, or BMI, a measure of body fat based on height and weight (4 per cent), high alcohol use and low physical activity (both 2 per cent).

In total, 28 per cent of the global breast cancer burden in 2023, equivalent to 6.8m years of healthy life lost to disability, illness and early death, was linked to six potentially modifiable risk factors.

Kayleigh Bhangdia, from the Institute for Health Metrics and Evaluation at the University of Washington and lead author of the study, said: “Breast cancer continues to take a profound toll on women’s lives and communities.

“While those in high-income countries typically benefit from screening and more timely diagnosis and comprehensive treatment strategies, the mounting burden of breast cancer is shifting to low- and lower middle-income countries where individuals often face later-stage diagnosis, more limited access to quality care and higher death rates that are threatening to eclipse progress in women’s health.”

New breast cancer cases in women are predicted to rise by about a third globally, from 2.3m in 2023 to more than 3.5m in 2050, according to the analysis by the Global Burden of Disease Study Breast Cancer Collaborators.

The findings suggest maintaining healthier lifestyles, including not smoking, doing sufficient physical activity, reducing red meat consumption and maintaining a healthy BMI, could help prevent more than a quarter of healthy years lost to illness and premature death due to breast cancer worldwide.

In the UK, about one in seven women will develop breast cancer during their lifetime.

The figures follow earlier research by Cancer Research UK which found that more than four in 10 UK cancer cases could be prevented through lifestyle changes.

The analysis also found that in 2023, three times as many new breast cancer cases were diagnosed in women aged 55 or older compared with women aged 20 to 54, with 161 cases per 100,000 women compared with 50.

However, rates of new cases among women aged 20 to 54 have risen by nearly a third, or 29 per cent, since 1990, while rates among older women have not changed substantially.

Claire Rowney, chief executive of Breast Cancer Now, said: “This new global study is a stark reminder that breast cancer is a disease that continues to take and rip apart far too many lives, not just here but around the world.

“We’re determined to realise our bold ambition that by 2050, everyone with breast cancer will live and live well, and we’re accelerating progress through building global collaborations with researchers and funders, as together we can go further, faster to ensure that every woman, no matter where she lives, can access early diagnosis, effective treatment and the support she needs.”

Sophie Brooks, health information manager at Cancer Research UK, added: “These figures are a sad reminder of the heavy toll breast cancer continues to take on women around the world.

“Prevention remains a key way to reduce rates, with a significant number of cases globally linked to preventable factors like smoking, overweight and obesity, and alcohol.”

Very heavy or very light periods may be linked to underlying health problems that affect quality of life and can influence fertility, according to medical experts.

Heavy menstrual bleeding is reported to have a major impact on daily life, with around two thirds of affected women seeking medical help. Beyond anaemia, which can cause fatigue, dizziness, pallor and a rapid heartbeat, heavy bleeding can lead to social and practical difficulties such as stained clothing, higher use of menstrual products and work limitations.

Doctors stress that the amount of bleeding itself does not directly affect fertility. Instead, abnormal bleeding can reflect underlying conditions, some of which can make it harder to become pregnant.

Raúl Villasevil, a specialist in obstetrics and gynaecology at San Carlos Clinical Hospital in Madrid, Spain, said: “The most frequent causes of heavy periods are polyps, fibroids, adenomyosis, some malignant tumours, ovulatory and coagulation problems, endometrial disorders, and certain medications.”

Very light periods can also signal problems, including uterine malformations, intrauterine adhesions, where scar tissue forms inside the womb, and anatomical abnormalities of the vagina. They may also point to ovulatory and hormonal disorders such as hyperprolactinaemia, which involves excess production of the hormone prolactin, or polycystic ovary syndrome. Once confirmed, these conditions can lead to symptoms including infertility.

To identify the cause of abnormal bleeding, Villasevil said doctors begin with a detailed personal and gynaecological history, followed by a physical examination and usually an ultrasound to assess the uterus and ovaries. Blood tests are also used to check for anaemia, coagulation status and hormonal function.

“This basic evaluation is often sufficient to establish the cause of the bleeding abnormality and to propose solutions. If this basic workup does not identify the cause, additional tests such as hysteroscopy or magnetic resonance imaging can be performed,” he added.

Hysteroscopy involves inserting a small camera into the womb to examine it from the inside.

In most cases, the cause of menstrual abnormalities can be identified and treated. A range of treatments allow a personalised approach for each woman, taking into account whether she wishes to have children, her age and her individual needs at different stages of life.

A non-hormonal radiofrequency treatment improved sexual function and vaginal health in postmenopausal women, according to results from a small randomised study.

The study assessed nonablative capacitive-resistive monopolar radiofrequency, an energy-based treatment that delivers controlled heat to vaginal tissue to improve blood flow and tissue health. It was tested as a potential treatment for genitourinary syndrome of menopause, a condition linked to reduced oestrogen that can cause dryness, irritation and pain during sex.

In the trial, 62 women with genitourinary syndrome of menopause were randomly assigned to receive either six weekly sessions of the active treatment, involving 32 women, or a sham procedure involving 30 women.

Women who received the radiofrequency treatment recorded larger improvements in sexual function, measured using the Female Sexual Function Index, than those in the sham group, both immediately after treatment and at a 12-week follow-up. Average scores increased by 5.86 points after treatment compared with 1.33 in the control group, and by 4.41 points at follow-up, while scores in the sham group declined slightly.

Vaginal health scores showed a similar pattern, with improvements of 4.75 points after treatment and 6.90 points at follow-up, compared with little or no change among women who received the sham procedure.

The research was carried out by scientists at the University of Castilla-La Mancha in Toledo, Spain. They reported no adverse events during the study and found no significant changes in participants’ oestrogen levels.

Stephanie Faubion, medical director for The Menopause Society, said: “This small study provides preliminary evidence on the effectiveness of nonablative radiofrequency on vaginal health and sexual function in postmenopausal women. Additional studies in larger and more diverse cohorts with multidimensional outcome assessments and longer-term follow-up are needed to confirm clinical applicability.”