In the general population, maintenance of a healthy weight is supported by eating a wide range of nutritious foods, and minimizing the consumption of highly processed foods that are calorie dense and nutrient poor, while balancing this with physical activity.1-4 Physical activities may also help to relieve stress and increase social interactions with others.
Maintaining weight for health with MND can be challenging. Research and experience shows that, generally, MND is associated with a loss of weight.5 Weight loss may indicate more rapid progression of the disease5 and potentially shorter survival.6 For some people with MND, significant weight loss might occur prior to the onset of signs of MND.7 For others, more noticeable weight loss occurs towards the end of life, but this varies between individuals.8
Weight loss with MND can occur for a variety of reasons. MND affects the neurons that are needed to maintain muscle function, and so weight loss is commonly due to loss of muscle mass. However weight loss might also occur due to loss of fat mass, which is a sign of not consuming enough energy.9 The degeneration of motor neurons affects muscles that control swallowing, and therefore eating and drinking can become more difficult.6 Difficulty with eating and drinking limits the ability of the body to receive the nutrition required to maintain a healthy weight.10, 11
Studies have found that some people with MND might also lose their appetite, resulting in weight loss.12 Low mood or depression can also cause a loss of appetite6, however loss of appetite could be due to factors that we don’t yet understand.13, 14
Appetite is controlled by factors released by our bodies, and mechanisms in our brain that sense and respond to these factors. Studies suggest that changes in function of the hypothalamus (a part of the brain that helps regulate important bodily functions such as appetite and energy use) or neuroendocrine feedback (interactions between the brain and the hormones release by our bodies that influence hunger and satiety) may also affect weight.15 Research indicates hypermetabolism is common among people living with MND, however this may not always contribute to weight loss.16
Lack of awareness of potential weight loss with MND can also occur. Some people living with MND, their carers and other supporters may need access to information, including information about swallowing function, and appropriate healthy diet options. Communication about nutrition can be challenging due to the need for nuanced and appropriate approaches when sharing information about ways of living with MND.17
Greater support for people providing care to those living with MND may also help with the management of swallowing.11
As part of care for MND, it is important for nutrition and weight maintenance needs to be addressed at the time of diagnosis, and monitored regularly with the help of a speech pathologist, dietitian and occupational therapist.5, 18, 19 However, with monitoring of weight and with appropriate support from the healthcare team will help to maintain a healthy weight when living with MND, which can contribute to longer life.20
People living with MND who are at later stages of the disease are at a higher risk of malnutrition, and require close nutritional monitoring.18 It is also harder to assess weight when standing up is difficult or not possible, which means there is a need for more careful monitoring and support.18
A mindful, supportive approach to maintaining weight for health with MND is recommended. People living with MND can best maintain a healthy weight by working with their healthcare team.21
Speech pathologists, dietitians and other health professionals involved in the care of people living with MND can support healthy weight of their patients by involving them in decision-making for care and support. Evidence suggests that shared decision-making can help increase a sense of control and comfort in dealing with changes to diet for managing weight, as well as improving ones understanding of how to best manage nutrition when living with MND.17
There is a need for more research into how best to support people with MND meet their dietary requirements. While it is tempting to introduce high calorie foods, including fast food, it is important to recognise that these diets might often have a negative impact on the quality of nutrients that people need to sustain health. As such, it is critical that people with MND consider working with their health professionals as they develop their dietary strategy.
Specifically, health professionals can support weight management for MND with:
Health professionals can best advise on, and help with, the introduction of enteral feeding options (such as percutaneous endoscopic gastrostomy tubes or radiologically inserted gastrostomy), which are helpful for addressing problems with swallowing and for maintaining nutrition, particularly for those using long term ventilator support.5, 8, 21
Enteral feeding involves the use of short, permanent tubes that are placed into the stomach through the abdominal wall. Liquid feeds and fluids can be passed through the tube, directly into the stomach, bypassing the mouth and throat. These tubes can be placed early, when surgery is safe, so that they can be ready for use once or if needed.23 For some, having a feeding tube provides an opportunity to support feeding, while still being able to eat.
The healthcare team can also work with people living with MND to help develop strategies for weight management that meets the needs of carers, family and loved ones, and for reducing stress and worry associated with weight loss and meal times.