How To Eat: Why the Most Effective Diet Isn’t Extreme, It’s Consistent

By Dr Natalie Hutchins

Quality evidence for what women should be eating

Open any social media app and you’ll find an entire universe of dietary dogma aimed at women. Keto for hormones. Carnivore for inflammation. Raw vegan for fertility. Seed-cycling for your cycle. Every tribe claims certainty, and every influencer offers a solution more absolute than the last.

But when you step away from the noise and examine the highest quality evidence across women’s health- from PCOS to endometriosis, from fertility to menopause, from metabolic disease to longevity- a remarkably consistent pattern emerges.

Despite our shifting hormonal landscape and changing nutritional needs across decades, the dietary pattern that best supports women’s health is fundamentally the same at every life stage is a plant-predominant, minimally processed, fibre-rich diet, built on whole grains, vegetables, fruit, legumes, nuts, seeds, healthy fats, and moderate amounts of lean or plant protein. 

This is the pattern repeatedly supported by prospective cohort studies, randomised controlled trials, large population datasets, and mechanistic research. It is also the dietary pattern seen in the longest-lived populations in the world.

Here’s how the evidence stacks up across the conditions women ask about most.

PCOS: Improving Insulin Resistance and Reducing Inflammation

PCOS is one of the clearest examples of a condition where dietary pattern significantly influences symptoms and long-term risk. At its core, PCOS is characterised by insulin resistance, chronic low-grade inflammation, and hormonal imbalance and diet affects all three.

Research consistently shows that high-fibre, low–glycaemic index diets improve insulin sensitivity, reduce circulating androgens, and support menstrual regularity ¹. Fibre acts not only by slowing glucose absorption but also by modulating the gut microbiome, which plays a direct role in metabolic and inflammatory pathways.

Mediterranean-style diets; rich in vegetables, legumes, wholegrains, olive oil, nuts, and fish, have been shown to lower inflammatory markers such as CRP and IL-6 in women with PCOS ², while also supporting weight management without imposing rigid restriction.

In contrast, diets high in ultra-processed foods, refined carbohydrates, and sugary beverages worsen insulin resistance independent of calories ³, amplifying the metabolic challenges women with PCOS already face.

Endometriosis: Modulating Inflammation and Hormonal Pathways

Endometriosis is a chronic, inflammatory, oestrogen-driven condition. Although no diet can cure it, the evidence for dietary modulation of inflammation, pain, and symptom severity is steadily growing.

High-fibre diets can support oestrogen metabolism by increasing faecal excretion of oestrogen metabolites ⁴, potentially reducing oestrogenic stimulation of endometrial lesions. Fibre also feeds the gut microbiome and given emerging research linking the gut–pelvic axis to endometriosis-related inflammation, this matters.

Omega-3 fatty acids from fish, nuts, and seeds have been associated with lower endometriosis risk and reduced inflammatory prostaglandin production ⁵, supporting a biochemical mechanism for symptom improvement.

Meanwhile, high intake of red and processed meat, particularly processed meats rich in trans fats, is associated with higher risk and greater symptom burden ⁶.

Diets rich in antioxidants, polyphenols, and plant diversity, such as the Mediterranean diet, have demonstrated improvements in pain scores, quality of life, and inflammatory markers ⁷.

Fertility: Supporting Ovulation, Hormonal Regulation, and Egg Quality

 

Few areas of nutrition have been studied as rigorously as fertility, thanks in large part to the Nurses’ Health Study, which identified the now well-known “Fertility Diet”.

This pattern- high in wholegrains, plant proteins, unsaturated fats, and high-fibre carbohydrates- was associated with a >60% lower risk of ovulatory infertility⁸.  Importantly, this wasn’t a low-carb or high-fat strategy: it was a balanced, plant-forward pattern that supported stable insulin dynamics and reduced inflammation.

Additional studies show that women undergoing IVF who follow a Mediterranean-style diet experience higher clinical pregnancy and live birth rates ⁹. The proposed mechanisms include improved insulin sensitivity, lower inflammatory load, enhanced micronutrient intake, and improved vascular health, all essential for folliculogenesis, endometrial receptivity, and early embryo development.

Conversely, diets high in ultra-processed foods, trans fats, and refined sugars impair ovulation and worsen metabolic health, particularly in women with underlying PCOS.

Menopause: Cardiometabolic Health, Weight, and Long-Term Disease Risk

Menopause marks a profound shift in women’s physiology. As oestrogen levels fall, cardiometabolic risk rises sharply. Women become more susceptible to central fat deposition, dyslipidaemia, impaired glucose regulation, and vascular ageing. Because cardiovascular disease is the leading cause of death in women, dietary pattern in midlife carries enormous long-term consequence.

The PREDIMED trial, showed that a Mediterranean diet supplemented with olive oil or nuts reduced major cardiovascular events by 25–30% ¹⁰. This dietary pattern improves LDL, triglycerides, insulin sensitivity, endothelial function, and inflammatory biomarkers; all of which deteriorate during the menopause transition.

Fibre-rich diets also support weight maintenance, which is independently associated with reduced vasomotor symptoms such as hot flushes, likely via thermoregulatory and metabolic pathways ¹¹.

Meanwhile, increasing consumption of ultra-processed foods is strongly linked to higher cardiovascular disease, diabetes, obesity, and all-cause mortality ^12,13. These risks compound during menopause, making dietary quality more important than ever.

What About Diet & Cancer Risk?

When examining cancer prevention and survivorship, the evidence once again points toward the same broad dietary pattern that supports women across their reproductive and metabolic life stages. Large-scale analyses from the World Cancer Research Fund/AICR; the most authoritative global body on diet and cancer consistently show that diets rich in whole plant foods, with high fibre, minimal red and processed meat, and low ultra-processed food intake, reduce the risk of multiple cancers, including breast, colorectal, endometrial and ovarian cancers¹⁴.

Meta-analyses of Mediterranean dietary patterns demonstrate reductions in both cancer incidence and cancer-specific mortality, likely through mechanisms involving reduced inflammation, improved insulin sensitivity, lower IGF-1 signalling and enhanced gut microbiome diversity ¹⁶.

For women who have already been diagnosed with cancer, emerging evidence¹⁵ suggests that a plant-predominant, fibre-rich diet may reduce the risk of recurrence, particularly for breast and colorectal cancers,  by improving metabolic markers, lowering chronic inflammation, and supporting immune surveillance. Diets high in ultra-processed foods and refined carbohydrates, by contrast, are associated with higher risk of recurrence and overall mortality in survivors.

 

Longevity: What Actually Extends Women’s Lifespan?

 

If we zoom out from specific diagnoses and life stages to look at what influences women’s health across decades, the clearest evidence lies in longevity research.

Large meta-analyses show that adherence to a Mediterranean dietary pattern reduces all-cause mortality, cardiovascular mortality, and cancer risk ¹⁷. These findings are echoed in the Blue Zones, the regions of the world with the highest proportion of people living past 100. Their diets share the same hallmarks: abundant vegetables, legumes, wholegrains, nuts, seeds, herbs, and minimal processed foods or refined carbohydrates.

Fibre is a major longevity lever: high-fibre diets reduce risk of premature mortality by up to 30% through improvements in metabolic, cardiovascular, and gut microbiome health Fibre is a major longevity lever: high-fibre diets reduce risk of premature mortality by up to 30% through improvements in metabolic, cardiovascular, and gut microbiome health.. Less than 10 percent of adults in the developed world meet their fibre targets.

The picture is remarkably consistent across geographies, populations, and methodologies: women who eat predominantly plants, healthy fats, and whole foods  and who limit refined carbohydrates and ultra-processed foods, live longer, healthier lives.

So, Do Women Need Different Diets for Different Life Stages?

No.  Women’s health changes profoundly through the decades but the nutrition that sustains us does not have to be complicated.  Although the ‘mediterranean diet has been mentioned many times in this article though, the fundamentals of this dietary pattern can be adapted to suit your individual preferences and cultural background; it is not a one size fits all thing.

However, it is clear that from PCOS to peri-menopause, fertility to longevity, the foundational principles are strikingly stable:

• A plant-predominant diet improves metabolic and hormonal balance.

• Fibre supports insulin sensitivity, oestrogen metabolism, gut health, and weight regulation.

• Healthy fats reduce inflammation and support cardiovascular and reproductive health.

• Whole, minimally processed foods reduce disease risk across every decade.

• Ultra-processed foods consistently worsen metabolic, cardiovascular, and inflammatory outcomes.

Our nutritional needs shift but the pattern that best supports our physiology does not.

References:

PCOS & Metabolic Health

1. Fan Y, et al. Dietary patterns in PCOS: systematic review of RCTs. Front Endocrinol. 2021.

2. Hall KD, et al. Ultra-processed diets cause excess calorie intake and weight gain. Cell Metab. 2019.

Endometriosis & Inflammation

4. Harris HR, et al. Fibre intake and endometriosis risk. Human Reprod. 2020.

5. Missmer SA, et al. Fat intake and endometriosis risk. Hum Reprod. 2010.

6. Parazzini F, et al. Diet and endometriosis: Systematic review. Reprod Biomed Online. 2021.

7. Trabert B, et al. Dietary fat and endometriosis risk. Am J Obstet Gynecol. 2011.

Fertility & Reproductive Outcomes

8. Chavarro JE, et al. Diet and ovulatory infertility: Findings from the Nurses’ Health Study. Am J Obstet Gynecol. 2007.

9. Karayiannis D, et al. Mediterranean diet and IVF success. Hum Reprod. 2018.

Menopause, Cardiometabolic Health & Long-Term Disease Risk

10. Estruch R, et al. Primary prevention of cardiovascular disease with a Mediterranean diet (PREDIMED). N Engl J Med. 2013.

11. Estruch R, et al. Retraction and republication of PREDIMED. N Engl J Med. 2018.

12. Newton KM, et al. Diet, weight, and vasomotor symptoms. Menopause. 2021.

13. Monteiro CA, et al. Ultra-processed foods and cardiometabolic disease risk. Public Health Nutr. 2019.

Diet and Cancer Prevention

14.  World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR). Continuous Update Project. Diet, Nutrition, Physical Activity and Cancer Prevention. 2018–2023 Reports.

15. Zhang X, et al. Plant-based diets and cancer risk: Meta-analysis. JAMA Netw Open. 2022.

16. Schwingshackl L, et al. Mediterranean diet and cancer risk: Meta-analysis. Br J Cancer. 2017.

Longevity, Mortality & Dietary Patterns

17.  Schwingshackl L, et al. Umbrella review of Mediterranean diet and mortality. Eur J Epidemiol. 2019.

18. Reynolds A, et al. Fibre intake and mortality: Systematic review and meta-analysis. Lancet. 2019.

19. Afshin A, et al. Global burden of dietary risks. Lancet. 2019.