Dancing with Poor Nutrition - Risks and Recommendations

Dancers consume fewer calories than they expend (Dahlstrom et al., 1990; Beck et al., 2015;  Hassapiduo et al., 2001; Doyle-Lucas et al., 2010; Brown et al., 2017) due to busy schedules, deliberate calorie restriction, pressure to maintain  low body weight, and a lack of knowledge. Taking class on an empty stomach increases muscle breakdown, which is undesirable for dancers who need strength to dance. It is critical that dancers consume carbohydrates prior to training to reduce muscle fatigue and help preserve muscle fibers that generate power for jumping. The purpose of a pre-exercise meal - consumed within an hour or less before training - is to hydrate, top off glycogen stores, and decrease hunger. If you take a class early in the morning, you have most likely fasted overnight and will need carbohydrates to help fuel your first class. Consuming carbohydrate spares the use of protein for energy, thereby freeing up protein to synthesize muscle and repair tissue. Poor nutrition may result in the following consequences:

• Delayed recovery – Overtraining and reduced caloric intake can result in delayed muscle rebuilding/recovery which can cause reduction in strength and endurance.  
• Immune dysfunction - Dance training produces stress hormones that trigger the release of stored energy. If these stress levels remain high, immune function can be impaired.
• Reproductive health - Females with inadequate nutrition may stop menstruating, thus compromising bone health and reproductive function (Doyle-Lucas et al., 2010).
• Stress fractures – Lack of caloric intake before class increases susceptibility to muscle fatigue. Improper technique, stress, muscle fatigue, and inadequate calcium/vitamin D intake increases the risk/frequency of stress fractures.
• Weak nails, brittle hair, dry skin - Insufficient protein and micronutrient intake leads to compromised health of nails, hair, and skin. Once the nutrient deficiency is corrected, these issues usually resolve quickly.

Recommendations
Dancers should consume about 15 calories per pound body weight, plus the training energy expenditure, which is approximately 200 calories per hour of class or rehearsal. For example, a 130-pound (60-kg) dancer might need 1,860 calories per day plus an additional 500 to 800 calories to meet the demands of class, rehearsal or performance that day, for a total of 2,360 to 2,660 calories. Nutrition needs are very individualized, so it is important that dancers seek dietary advice from qualified specialists (i.e., a Registered Dietitian for dancers).
References:
Brown, M. A., Howatson, G., Quin, E., Redding, E., & Stevenson, E. J. (2017). Energy intake and energy expenditure of pre-professional female contemporary dancers. PLoS ONE, 12(2), e0171998.
Dahlstrom M, Jansson E, Nordevang E, Kaijser L. (1990). Discrepancy between estimated energy intake and requirement in female dancers. Clinical physiology; 10(1):11-25. Epub 1990/01/01.
Hassapidou MN, Manstrantoni A. (2001). Dietary intakes of elite female athletes in Greece. Journal of human nutrition and dietetics: the official journal of the British Dietetic Association;14(5):391-6. Epub 2002/03/22.
Kostrzewa-Tarnowska A, Jeszka J. (2003). Energy balance and body composition factors in adolescent ballet school students. Polish Journal of Food and Nutrition Sciences;12(3):71-5.
Beck KL, Mitchell S, Foskett A, Conlon CA, von Hurst PR. (2015). Dietary Intake, Anthropometric Characteristics, and Iron and Vitamin D Status of Female Adolescent Ballet Dancers Living in New Zealand. Int J Sport Nutr Exerc Metab; ;25(4):335-43. Epub 2014/11/12. doi: 10.1123/ijsnem.2014-0089 25386731
Doyle-Lucas AF, Akers JD, Davy BM. (2010). Energetic efficiency, menstrual irregularity, and bone mineral density in elite professional female ballet dancers. J Dance Med Sci;;14(4):146-54. Epub 2010/01/01. 21703085
Hirsch NM, Eisenmann JC, Moore SJ, Winnail SD, Stalder MA. (2003). Energy Balance and Physical Activity Patterns in University Ballet Dancers. Journal of Dance Medicine & Science;7(3):73-9.
Sousa, M., Carvalho, P., Moreira, P., Teixeira, V. (2013). Nutrition and Nutritional Issues for Dancers. Medical Problems of Performing Artists, 28, 119.
Montanari, A., & Zietkiewicz, E. A. (2000). Adolescent South African ballet dancers. South African journal of psychology, 30(2), 31-35.

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