Hot and humid seasons, dehydration and loss of electrolytes


As a rule, hot and humid seasons record increasing cases of malaise and disorders linked to altered hydro-electrolytic balance. All population groups are at risk – more so in recent years due to worsening climate change.
As a result, a significantly higher amount of fluids is transferred to the outside environment (with body weight fluctuations up to kilograms in a single day). Besides being sizeable, these changes develop very fast, which often limits the ability to mitigate their consequences due to the disproportion between the amount of water and micro-elements lost by the body and their daily intake.
In this regard, one of the first issues that physicians or nutritionists are called upon to consider is an evaluation of the patient’s general state of hydration.
Over the last few years, supplementation has become an indispensable tool to ensure that our body has all the nutrients it needs. As a rule, hot and humid periods record increasing cases of malaise and disorders linked to altered hydro-electrolytic balance; as a result, the body is more prone to essential nutrients deficiency or even the onset of Medically Unexplained Symptoms (MUS) such as tiredness and fatigue. Proper supplementation is therefore the way forward for maintaining good health.
Vitamins and minerals are essential for normal biological functions: group B vitamins are important for proper metabolism of carbohydrates, lipids, proteins and iron; vitamin C is an excellent antioxidant and is fundamental for maintaining in good condition the immune system; calcium is useful for neurotransmission, cell division and for the bone tissue; chromium is indispensable for maintaining normal levels of glucose; iron helps  energy metabolism, transports oxygen, reduces tiredness and fatigue; potassium and magnesium are indicated for maintaining good hydro-saline balance and are involved in normal muscular, cardiac, neurological and gastrointestinal functions.
Proper vitamin and mineral supplementation can therefore be useful in a variety of situations such as in case of hydro-saline imbalance, persistent tiredness, medically-unexplained symptoms, altered energy metabolism or altered extracellular pH.

Hydro-saline balance

Water is the main constituent of our body (accounting for approximately 50-60% of the body weight of an adult) (TBW-body hydration) [1] and performs actions of fundamental importance. Indeed, it enables the transport of nutrients through cell membranes, regulates temperature and is the medium through which numerous biochemical reactions occur. In addition, it is key for the cardiovascular function (as it regulates blood pressure) (ECW – extracellular water) [1] and digestion. 
The hydro-electrolytic balance changes all the time because we lose water when we breathe, sweat and urinate and take in water with the liquids we drink and the food we eat (TBW-Total Body Water Turnover) [1]. When the loss of water is not offset by adequate liquids intake, we risk dehydration and the whole body suffers from this [2,3]. Dehydration can occur in any season of the year but we are more at risk in summertime when the requirement of liquids increases due more liquids being lost as a result of climate change.
Hence the importance of maintaining proper hydration and adequate hydro-electrolytic balance. Water supplementation alone is often not enough because when we sweat we also lose mineral salts, which is why magnesium and potassium supplementation is indicated for maintaining adequate hydro-saline balance (TBK - total body potassium, ECK - extra-cellular potassium, TBMg - total body magnesium, K/Mg Ratio potassium-magnesium ratio, TbNa - total body sodium) [1,4,5]; besides, potassium and sodium bicarbonate are useful as they help maintain the acid-base balance of the extra-cellular environment.

Supplements that comprise most group-B vitamins are indispensable in the metabolism of carbohydrates, proteins and lipids; vitamins C, E and beta carotene are excellent antioxidants and vitamin C is important in lipid metabolism, while copper and zinc are involved in the metabolism of carbohydrates. One should also be mindful that in order for the body to function properly, a good state of hydration is indispensable; besides, with their proper content of mineral salts such as potassium and magnesium, these supplements are indispensable above all in summertime when the requirement of liquids and mineral salts increases. In addition to dehydration, in summertime symptoms such as tiredness and fatigue can worsen; for this reason, group B vitamins, vitamin C and copper supplements are indicated not only because they are able, per se, to reduce the symptoms of tiredness, but above all because they are all involved in iron metabolism, the deficiency of which plays a role in this problem.
In addition, one should consider that any drug therapy entails varying degrees of  vitamin and/or mineral loss/deficiency and the resulting consequences.
So, these supplements, which include all the components described earlier,  allow to maintain optimal state of hydration and proper intake of minerals and vitamins that are indispensable for preserving a good state of health and well-being and can also be useful for:

  • physical recovery after sports activity;
  • supporting good mental performance;
  • maintaining in good condition the bones, cartilage and skin, thanks to vitamin C, calcium, magnesium and manganese;
  • strengthening the immune system;
  • helping maintain optimal blood pressure levels.

Authors: Dario Boschiero, Laura Converso - Date: 24/06/2016

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  1. Medical Device BIA-ACC Biotekna. TBW=Total Body Water, TBK=Total Body Kalium, ECK=Extra Cellular Kalium, TBMg=Total Body Magnesium, Ratio K/Mg: Potassium/Magnesium ratio, Tbprotein= Total Body protein, Le=essential Lipids, FM=Fatt Mass, Gly=Glycogen, ECW=extracellular water, Turnover TBW= turnover Total Body Water.
  2. J Am Coll Nutr October 2007. Assessing Hydration Status: The Elusive Gold Standard. Lawrence E.
  3. Physiol Behav. 2010 Apr 26;100(1):15-21. Epub 2010 Mar 6. Thirst and hydration: physiology and consequences of dysfunction. Thornton SN.
  4. The European Nutrition for Health Alliance.
  5. EFSA. Council of the european union. 27 Jannuary 2012.