Is there a potential nutritional deficiency? If a patient is hypothyroid, and usually cold- but is overweight (despite exercising) and now recently claims that she is unable to sweat- what could that indicate?
A decrease in sweating is typical in hypothyroidism. However, a change should be evaluated.
Decreased sweating may reflect dehydration so be sure to assess hydration status. Most individuals need at least ½ ounce of fluid per pound of body weight (30-35 mL/kg).
If she is drinking plenty of water/fluids and not sweating or urinating, then fluid retention must be evaluated. Also, investigate if her exercise intensity has decreased or if the environment in which she is exercising is cooler.
A decrease in sweating wouldn’t necessarily reflect a nutrient deficiency (except for water which is technically a macronutrient even though it doesn’t provide Calories).
However, sweating can cause a loss of nutrients, especially electrolytes (sodium, potassium, chloride, magnesium, calcium), vitamin C, and even iodine which may already be depleted in those with hypothyroidism.
Sweating is also part of the body’s detoxification system so a decrease in sweating could contribute to a buildup of toxins.
References:
Black, Janet L. "Detoxification and Biotransformation." Integrative and Functional Medical Nutrition Therapy. Humana, Cham, 2020. 205-212.
Genuis, Stephen J et al. “Clinical detoxification: elimination of persistent toxicants from the human body.” TheScientificWorldJournal vol. 2013 238347. 6 Jun. 2013
Mao, I F et al. “Electrolyte loss in sweat and iodine deficiency in a hot environment.” Archives of environmental health vol. 56,3 (2001): 271-7.
Patil, Nikita, et al. “Hypothyroidism.” StatPearls, StatPearls Publishing, 6 January 2021.