On The Trending Morning Beverage: Does Hot Water With Lemon Really Kick-start Your Metabolism?

             Hot water with lemon:  The "hot" morning drink trend.  Photo Credit:  Shape.com

  

Many social media trend-setters are claiming that drinking a cup of hot water with lemon each morning kick-starts their daily metabolism, "speeding" it up and helping them to burn energy and lose weight--but is there research to support the possibility that these claims could be true for their followers?

•  Studies published by Boschmann and colleages in one 2003 article investigated the effects of drinking water on bodily energy expenditure. The study supposed changes in blood pressure, as well as heat produced to warm cooled water to body temperature, following water ingestion lead to increases in metabolism in both men and women studied. The average energy used by participants after drinking ~2 cups of water was measured to be ~25 Calories. Though this small study had only 14 young adult participants and their outcomes from drinking water may not be typical for everyone or for other types of beverages, it is interesting that drinking water throughout the day may lead to a small increased use of energy and be helpful as part of a weight loss/maintenance plan (~100 Calories used per day?).

• Another article by Morris & Jay published in 2017 discussed the impact food temperature has on the body and food's role in body temp regulation; though there are "thermoregulators" located in the abdomen that sense the presence of hot or cold foods and fluids ingested, the temperature of foods may not directly affect body's temperature much, rather causing the body to initiate processes (e.g. sweating or shivering) that assist in adjusting body temperature, either not requiring the body to use energy or requiring little energy (Calories).

• A third article discussion by Bradley & Melby following a 2016 publication proposed that the temperature of foods and beverages people consume doesn't matter much to the grand scheme of metabolism since the body efficiently monitors and modifies its usual core temp (~98.6 degrees F) when it begins to vary, protecting the body from exerting significant energy (Calories) to maintain a temperature optimal for body function. Essentially, it is described that the body does its best to conserve energy. The conditions a person is in can affect the degree to which food temperature impacts body temperature (e.g. heated in exercise, chilled in hypothermia), but food temperature will ultimately have a greater effect when it is advantageous to the conservation of energy.  

Does this mean that hot and cold foods have a minimal impact on metabolism? Probably. Will drinking a few cups of hot lemon water each morning speed up your metabolism and help you to lose weight? Possibly, but perhaps not as much as someone might want.

As studies may not have investigated various age groups, defined exact temperatures for the terms "hot" and "cold," studied various compositions of heated/cooled foods and fluids, or studied the specific hot-lemon-water beverage and how it may influence metabolism or weight loss (considering the effects of lemon with vitamin C/ascorbic acid in states of vitamin deficiency or non-deficiency and how temperature would affect the stability of the vitamin), there is a lot of room for speculation.

If it was suggested that drinking lemon water at a temperature of boiling would speed up your metabolism, would you drink it? It may be too soon to jump on the hot water and lemon every day train just for its metabolism-boosting purposes or for a vision of quick, easy weight loss, but let's not forget that water is an essential part of a regular, healthy metabolism, temperature regulation, and more. Proper hydration may make some people feel fuller, reducing their appetite and leading to weight loss in a different way.
If you are fond of citrus or cozy beverages in the morning, lemon water could be a hydrating start to your daily routine! Most healthy persons need to drink ~2 liters of non-alcoholic fluids a day to stay properly hydrated; depending on the amount of lemon juice added, this morning beverage could put you on your way to achieving your recommended daily intake of fluids and vitamin C! Check out MyPlate online for more hydration & health information.

Also, see the first, second, or third research article(s) mentioned.