With PCOS or as it’s been renamed PMOS it needs to be treated as a metabolic condition,. One of the leading traits of PMOS is insulin resistance and so eating healthily may look different t what the NHS typically describe, particularly in relation to carbohydrates.
The best suggestion I can give is to have her look at Diabetes UK and other reputable Diabetes support for nutrition and exercise guidance. Generally a lower carb diet is recommended, not no carb, but lower carb and pairing them with a protein or fat, so a slice of seeded toast with scrambled egg or with peanut butter. Then a short brisk walk or other form of activity after the meal to help break down the sugar and increase metabolism.
If she’s overweight then losing 10% of her bodyweight can make a big difference in other symptoms of PMOS.
I was diagnosed through hormone levels and a scan of my ovaries when I was 27, I was trying to conceive and had very very irregular periods. I lost 10% of my weight and my periods returned and I was able to get pregnant.
It is hard going and would be significantly easier with medical support and medication like Metformin or Mounjaro but there are thinks she can do herself even if the Doctors won’t help. I have no personal experience of insotol or berberine supplements but have heard good things about both and they are available from Holland & Barrett and other similar shops.
If financially Mounjaro is an option for her then I can’t recommend it highly enough, I was diagnosed T2 diabetic in Aug 2024, Metformin, insulin and basically eliminating all carbs from my diet couldn’t get my sugar levels low enough so the diabetes team added Mounjaro to my prescription and within 6 weeks I was able to stop the insulin, 6 weeks after that I was able to stop the metformin and over the 18 months I’ve been on it I’ve lost 10 stone and for the first time since primary school I’m a healthy BMI.