Sitters often have difficulties with chewing and may get tired when eating. It is important they see a dietitian to advise on an appropriate individualised diet. Sitters who are children should have their nutrition status assessed every three to six months after their diagnosis and then annually.

If they have had choking or coughing episodes when they have been feeding or eating, sitters should have a swallow test (video fluoroscopic swallow study). Their diet, chewing and swallowing abilities should also be reviewed by a speech and language therapist who will recommend how food should be prepared in terms of its consistency (e.g. pureed or semi solid or thicker liquids such as milkshakes). The speech and language therapist will also advise on feeding modifications if necessary.

If an individual is showing signs that they are not growing well, a feeding tube should be considered so that they get the extra nutrition they need. If they can still swallow safely, they should also be encouraged to have some food by mouth.

As their ability to move around is reduced and their body composition is altered, sitters are at risk of becoming overweight. If they are showing signs of this, it is recommended that they should have blood tests to check how they are managing to process sugars (glucose metabolism).

If regular constipation is an issue, fluid and fibre consumption should be increased; talk to the medical team for advice. Medication to assist with bowel movement may also be helpful.

In the event of illness, it is important to consult the medical team about care and management as it is essential extra fluids are given early and that salts in the blood are monitored. Having SMA means that metabolising fat normally can be difficult and can sometimes lead to an excessive build-up of ketones and other byproducts. To avoid this, a steady diet with sugars and protein to limit the breakdown of fats to make energy is recommended. This is especially important during illness, and it is recommended that nutrition with sugars and protein is given within six hours of becoming ill and continued. Fasting should be avoided.