Did you know that by reheating your end-of-year dinners you may be increasing your risk of being overweight or obese, and also worsening your allergy symptoms?

The end of the year arrives, and with it family dinners, as well as gatherings between friends or work colleagues; it can happen that between so many celebrations, "leftovers" remain more than once, which is wonderful if we think that the next day it won't be necessary to cook... this food can be shared among the attendees, where each person will leave the celebration with a plastic container or airtight bag to reheat these meals the next day.

And so far so good; however, this daily occurrence could be affecting your hormonal and metabolic health more than you imagine, due to the presence of Endocrine Disruptors and an increased generation of Histamine. In addition, there are certain important considerations that, if unknown, can lead to Food Poisoning when reheating food.

According to the World Health Organization (WHO), an Endocrine Disruptor is an exogenous substance or mixture of substances that alters the functions of the endocrine system and, consequently, causes adverse health effects in an organism, its progeny, or subpopulations.

Human beings are exposed to endocrine disruptors throughout their entire life cycle, as they are found in various common sources, for example, personal hygiene products, household cleaning products, industrial chemicals, pharmaceuticals, environmental pollutants, and also in foods with pesticides, herbicides, fungicides, or plastics.

Some of the best-known endocrine disruptors are Bisphenol (BPA) and Phthalates, as they are in a wide variety of plastic consumer products. Although these disruptors are metabolized and excreted relatively quickly, because humans are constantly exposed, a chronic intake of these substances is generated throughout life.

Disruptors can affect any endocrine organ, hormonal system, or hormonal pathway; some can interfere with the regulation of metabolism, energy balance, and fat storage in the body.

Adipose tissue is not just a passive fat storage depot; it is also recognized as a large endocrine organ that secretes a large number of diverse hormones and bioactive molecules that play a critical role in regulating metabolism and body fat percentage. As the function of adipose tissue is affected and metabolic endocrine signaling is altered, there is, therefore, a greater risk of being overweight or obese.

Plastics are the main additives in the manufacture of food products; they are commonly used in the production of food packaging materials to improve flexibility, durability, processing, and resistance to heat, fire, and UV radiation.

All these chemicals derived from plastics can be released and leached into food after their degradation. Humans can be exposed to these disruptors through ingestion, the respiratory tract, and dermal exposure.

Exposure to BPA has been associated with a large number of disorders, such as obesity, type 2 diabetes, cardiovascular diseases, infertility, neurodegenerative diseases, and cancer, particularly breast cancer.

Furthermore, BPA is classified as a potentially toxic substance that is harmful to reproduction and the eyes, and as a substance possibly irritating to the skin and respiratory tract.

They are not firmly bound to plastic, so they can easily migrate into food, water, or air, meaning they can be ingested through food, inhalation, or dermal contact; some phthalates have the ability to cross the placenta, potentially exposing the developing fetus to these chemicals during pregnancy.

Obesogenic endocrine disruptors such as BPA and phthalates may be involved in the etiopathogenesis of obesity and associated metabolic disorders because they:

1. Increase the number and size of adipocytes through the regulation of genes involved in adipogenesis.
2. Modulate epigenetic pathways during development, which increases susceptibility to obesity.
3. Impact neuroendocrine signals responsible for appetite and satiety.
4. Promote a pro-inflammatory environment in adipose tissue and induce a state of chronic subclinical inflammation.
5. Contribute to the dysregulation of the gut microbiota and immune homeostasis.
6. Induce dysfunction in thermogenic adipose tissue.

Reheating food that is in plastic containers can increase the migration of endocrine disruptors (such as phthalates and BPA) from the containers into the food, since the heat generated in ovens or microwaves facilitates and accelerates the release of plastic-derived chemicals (BPA, phthalates) into the food.

Furthermore, fast and ultra-processed food, which often comes in plastic packaging, already contains these chemicals, and reheating it increases the risk.

• Use glass, stainless steel, or silicone (BPA/phthalate-free) instead of plastic to store and heat food.
• Use glass or stainless steel bottles for water and other liquids.
• Never place hot food in plastic containers or bags.
• Avoid plastic wrap.

Others:

• Choose natural cosmetics without "fragrance" or "parfum"
• Choose quality wood, bamboo, or silicone for children, and look for "BPA/phthalate-free" labels
• Look for natural or certified alternatives for cleaning products
• Prioritize cotton clothing over synthetic ones
• Read labels and look for "BPA-free" and "phthalate-free" packaging.

It is an essential molecule for various vital functions; it acts as a neurotransmitter, participates in immune responses, and is involved in the regulation of the digestive and cardiovascular systems.

It is found naturally in various foods, especially those that have undergone fermentation processes (wine, beer, vinegar, yogurt, kefir, sauerkraut), aging, such as cured cheeses (parmesan, roquefort, or gouda), processed meats (salami, cured ham), canned or smoked fish (tuna, sardines, mackerel), certain vegetables (tomato, spinach, eggplant, avocado), chocolate, citrus fruits, nuts, and soy derivatives.

Our body is capable of metabolizing histamine thanks to the action of diamine oxidase (DAO), an enzyme responsible for breaking it down in the small intestine. However, some people have a DAO deficiency, which prevents the proper elimination of histamine, leading to adverse symptoms such as headaches and migraines, digestive problems, chronic hives, nasal congestion, and causing reactions similar to allergies. This clinical condition is known as histamine intolerance or histaminosis.

Reheated food increases histamine because the bacteria present in food produce histamine during storage, a process that accelerates with time and temperature, especially in meat and fish.

Once histamine has formed in a food, it cannot be eliminated, as it is resistant to both thermal treatments like cooking and to various storage temperatures, including refrigeration and freezing.

Therefore, reheating a meal that already contains histamine will not reduce it. Consequently, the suggestion for people with DAO deficiency is to consume fresh food and then refrigerate it quickly to slow down the formation of histamine.

• Stay hydrated with water, as histamine concentration increases in the body when it is poorly hydrated.
• Avoid preservatives added to foods that are typically high in histamine. We suggest avoiding flavor enhancers (E-620 to E-625), as well as monosodium glutamate, as they hinder the elimination of histamine.
• Freeze properly (quickly), as low temperatures slow down the production of histamine, but subsequent reheating remains a problem.
• Every time food is reheated, histamine increases, so it is better to eat in small portions or avoid reheating.

1. Vitamin C curbs the release of histamine and promotes the effect of the enzyme that eliminates it.
2. Vitamin B6 helps DAO to be effective.
3. Quercetin helps to inhibit histamine release (found in onion, apple, broccoli, green tea).

When reheating food, bacterial proliferation and the formation of heat-resistant toxins can occur; this happens especially when food spends too much time in the so-called "danger zone," which is a range between 5°C and 63°C, or it can also happen if the food is not heated evenly.

To avoid food poisoning and nutrient loss, the best way to do this is to ensure the food reaches a minimum internal temperature of 74°C in all parts; that is why if you use a microwave, it is essential to stir or rotate the food halfway through the process to eliminate cold spots where bacteria could survive.

It is also important to reheat only the portion that is going to be consumed at that moment and avoid repeating the reheating cycle more than once.

Dalamaga, M., Kounatidis, D., Tsilingiris, D., Vallianou, N. G., Karampela, I., Psallida, S., & Papavassiliou, A. G. (2024). The Role of Endocrine Disruptors Bisphenols and Phthalates in Obesity: Current Evidence, Perspectives and Controversies. International journal of molecular sciences, 25(1), 675. https://doi.org/10.3390/ijms25010675

Martínez-Pinna, J., Sempere-Navarro, R., Medina-Gali, R. M., Fuentes, E., Quesada, I., Sargis, R. M., Trasande, L., & Nadal, A. (2023). Endocrine disruptors in plastics alter β-cell physiology and increase the risk of diabetes mellitus. American journal of physiology. Endocrinology and metabolism, 324(6), E488–E505. https://doi.org/10.1152/ajpendo.00068.2023

Jochum C. (2024). Histamine Intolerance: Symptoms, Diagnosis, and Beyond. Nutrients, 16(8), 1219. https://doi.org/10.3390/nu16081219

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