Adult malnutrition is a health problem, not a child protection issue. A child presenting to a doctor with malnutrition is always a child protection issue and it should be, but as an adult it is safe to see your doctor and ask to be checked over. You need to do this.
They will ask you questions designed to ascertain if you have an eating disorder, or substance misuse problems, and it is ok to say that you have not been prioritising yourself and not feeding yourself. They may also ask you questions about your children and their diet, and they do need to do this. The doctor will explore whether there are other underlying problems, and there may well be. While my malnutrition was very much poverty related, it was also related to long term stomach problems including gastritis and problems which developed in successive pregnancies.
From the moment your child is born, motherhood is a lesson in subordinating your needs to the needs of your child. This starts with sleep in babyhood, and with illness, and your body becomes well used to ignoring its basic needs.
Mothers have historically acted as shock absorbers of poverty, and it was that invisible willingness to sacrifice that austerity exploited, with all our political parties agreed that you could pay that price. This is not your fault and you can treat this.
You are not a failure as a parent if you have malnutrition, but you do need to address it because your children not only need you, they need a healthy you and will not thank you if you are sick on their behalf or end up with serious long term problems.
Just the act of eating and introducing nutrition to your body makes a huge difference very quickly, and you will be shocked at how much energy you have and how different things look and feel once you are eating what your body needs
Even if lethargy, brain fog, and headaches and other symptoms have affected the way you interact with your child, or the standards of your home, it can be sorted without it being a child protection issue.
If the symptoms of malnutrition have brought you into contact with social services before you got it addressed, social workers will look at whether you have addressed it and recognise what’s happened and they may be able to help get you seen by dietician sooner.
I still have occasional bouts of exhaustion, but I have successfully managed to bring my BMI to a healthy state within weeks, and had more energy than I have had in years after only a couple of days of eating.
Your child needs a healthy mum(or dad) and you deserve to be healthy.