Insomnia: is the current sleeping schedule of 8 hours good for the human being?

Insomnia is one of the biggest problems for health of the 21st century. Everyone knows the uncomfortable sensation of being awake in the middle of the night and having difficulties to sleep. It is common in specific periods, specially when we are nervous and stressed, whether we are preparing an exam or we have worries. However, there are people who suffer from sleeping disorders on daily basis, around 30% – 50% of the population suffers from chronic insomnia. 

After some researching, the question is: has the human being always slept for 7-8 in the night? Some experts have unveiled the so called “biphasic sleep”, there has been little discussion on this subject and you may wonder what is it about.

Biphasic sleep consists of two sleeping phases with an interruption in the middle of the sleep. Researchers have demonstrated that our ancerstors in the middle age used to sleep in two phases, they fell asleep at the beginning of the night and they woke up in the middle of the night. They used this interruption to read, to speak with their relatives, to pray, among other things. After this pause, they fell asleep again and they slept until the morning. 

This suggests that our sleeping routine has changed with time and our bodies are not used to sleep for 7-8 hours without interruptions. The historical event that led the emergence of monophasic sleep was the industrial revolution. Artificial light arised and our sleeping patters changed. Human being went to bed later and the time destined to sleep was reduced. Biphasic sleep disappeared and led to monophasic sleep.

Biphasic sleep is quite common between different animal species: many bird species, mammals and insect are biphasic sleepers. That means that our sleep patters are unnatural. This could be demonstrated through a study that selected several healthy individuals to sleep without artificial light (10 hours of light, 14 hours of darkness) and analyze their sleeping patterns. 

At first the participants slept an average time of 7,7 hours with a monophasic pattern. After some time of adaptation there were individuals who naturally changed their monophasic sleep for a biphasic sleep, the average time of sleeping increased until reaching a period of 11 hours and it was observed that participants interrupted their sleep during one to three hours and then they slept again.

Monophasic sleep may have some disadvantages, we dedicate less time to sleep and there are people who have a biphasic or polyphasic pattern, resting less. The body is regulated by two hormones: melatonin and cortissol. The first one is responsible for telling our body that we have to sleep, cortissol has the opposite function, it activates our bodies telling us that we have to stay awake. The body expossure to artificial light decreases our melatonin levels, this make sleeping difficult for us and we tend to go to bed later. 

In a nutshell, these are good news for people who suffer from chronic insomnia, waking up at the middle of the night is something natural, the human body has had no time to adapt to a monophasic pattern and some of us interrupt our sleep naturally.

To improve our sleep quality it would be necessary to readapt our lifestyle to the natural cycle. How can this be done? Expossure to artificial light should be reduced (yes, this includes our cell phones and electronic devices) to readjust our melatonin levels, it is recommended to stop using our electronic devices around 30-60 minutes before we go to bed, it is also important to follow a regular schedule going to be always at the same time.

Written by Sara García Sánchez

Message to reader: Any information on this blog is for informational purposes only. It is not intended in any way to replace professional figures in the medical and consultancy fields.

Messaggio al lettore: Ogni informazione presente in questo blog è puramente a scopo informativo. Non si intende in nessun modo sostituire figure professionali in campo medico e di consulenza.

Language and the brain: benefits of being bilingual

One of the main characteristics that distinguishes human beings from animals is the use of communicating through a language. Language is a complex system that helps us to express feelings and ideas using the words in an orderly manner. Animals can communicate between them using sounds or smells. However they haven’t reached the ability of using specific sounds to define an object, feeling, action or specific characteristics creating a structured system, giving us the ability to express feelings and ideas. 

Many hypotheses have been created trying to explain the origin of the language. It is said that the first words could have been created by transforming the sounds of animals and objects into vocal sounds, trying to imitate them. Another popular belief says that the first words were interjections that expressed pain, happiness, anger, sadness. Despite that, it is hard to know the origins of language, there is no written evidence, all the hypotheses are based on comparisons between animal communication and the biological evolution of the human being.

One thing is clear, the ability of speaking a language was possible due to an increase in the size of the human brain. There is a specific region of the brain destined to the language, this region is divided in the Wernicke’s area, the Broca’s area and the angular gyrus. The Wernicke’s area function consists of the comprehension of the spoken language, while the Broca’s area is involved in the comprehension of grammar, the processing and the oral transmission of the language.

As we have seen above, language is a complex system. For this reason we wonder, how does the brain of someone who speaks more than one language work? There are different types of bilingualism.

• The first type belongs to people who have learnt two languages simultaneously in their childhood.
• There is a second group for people who have learnt a language during puberty.
• The last group consists of people who have learnt a language in their adulthood (after the 20 years old).

Years ago, bilingualism was not considered good for children, since the general thought was that it could be confusing for children. However, researchers have discovered that learning a second language has many benefits in our brains, from childhood to old age. Children who speak a second language have a better ability to focus on doing a task, instead, monolingual children can be distracted more easily. It has been proven that bilingualism helps to prevent disorders like dementia or Alzheimer.

Many questions have emerged in relation to bilingualism. The first one would be, is the second language stored in the same regions of the first language? Several studies have shed some light on this, discovering that the ability of speaking a second language is developed in the same brain regions. 

These studies show that speaking more than one language changes the brain structure. It has been observed that bilingual brains have a denser grey matter, specially in the left side of the brain, where language functions are developed. This effect is even more dramatic in the first group, people who learnt a second language simultaneously in their childhood, and in people who reached a proficiency level. 

The benefits also appear in adulthood. For this reason, it is never too late to learn a new language, even if you are already an adult. Learning a language in adulthood helps to improve the brain function, providing a better memory and more mental flexibility. In the case of adults, the ability of speaking a second language is developed in an area next to the first language centers.

To conclude with the article, it would be necessary to make a reflection. Children and teenagers have a more flexible brain. It has been proven that the better age for learning a language reaches its peak at 10 years old, after this age the plasticity of the brain decreases year after year. This is the perfect age to control the language as a native speaker, making no grammar mistakes and having a good pronunciation. 

Although the general thought says that it is late to learn a language when you grow up, the adult brain can provide some advantages to learn a language. Children have less cognitive skills, as adults we can better understand complex situations and this helps us to better understand grammar rules, as it is said, “old dog new tricks”. In addition to this, while children can be easily distracted, adults put more attention on learning for longer periods, this is influenced by the real interest of someone for the language. 

In other words, children acquire language by imitation, listening native speakers, they have a better memory and a better capacity to imitate phonetic sounds. However, problem solving and analytical skills are developed with age, these can be quite useful to learn a new language, helping us to really understand how language works. For this reason, if you are thinking about learning a second language, it does not matter if you are a teenager or if you are already an adult, it is never too late to start.

Written by Sara García Sánchez

Message to reader: Any information on this blog is for informational purposes only. It is not intended in any way to replace professional figures in the medical and consultancy fields.

Messaggio al lettore: Ogni informazione presente in questo blog è puramente a scopo informativo. Non si intende in nessun modo sostituire figure professionali in campo medico e di consulenza.

COVID vaccines: how does immunity work?

Vaccines are composed of inactive viruses or bacteria or fragments of these microorganisms which helps to protect the body in future infections. In other words, vaccines are a learning for our immune system, the body reacts to the inactive pathogen creating specific “defenses”.

When we get vaccinated, we create several types of “defenses”. The most important are the antibodies and the memory T cells.

The antibodies are a type of glycoproteins which are part of the “defenses” of the immune system, they are produced by the B lymphocytes. They work by recognizing a specific part of the pathogen, also called antigen. There are different processes that lead to the neutralisation of the pathogen, these are: agglutination, precipitation, opsonization and neutralisation. After the first infection, the body takes some time to react and produce specific antibodies.

The antibodies have a specific immunity, each one identifies one specific pathogen, unless it were a variety of an already known pathogen. We have thousands of types of antibodies and we produce new antibodies when we are infected by an unknown pathogen that hasn’t infected us before. For this reason we are vulnerable to new illnesses.

the antibodies

After the first infection our immune system developes memory. The T cells participate in the inmune reaction producing memory T cells. There are inmature T cells in the bone marrow that migrate to the lymphatic ganglia where are exposed to the antigen. Then they are activated and the clonal expansion begins and they migrate to the infected organ. The T cells eliminate the pathogen and then die of apoptosis. There is a small percentage that remains after the infection, becoming the memory T cells.

These cells are the key of the success of the vaccines. They work as mediators in the following infections recognising the pathogens. After the vaccination, antigens and memory T cells are generated. The antibodies remain in the blood some time after supplying the vaccine and the disappear. The memory T cells remain in the body for a longer time. When we are infected, the memory T cells recognise the pathogen and the inmune reaction starts, producing the antibodies. This second reaction is produced faster due to the previous learning of the vaccines.

Talking about the COVID vaccines. When we see news telling that after four or five months the antibodies levels decrease it is not surprising, since the antibodies are the remains of the natural infection or the vaccines. The key to understand their function is the immunity mediated by memory T cells. These cells are responsible of a milder illness.

Written by Sara García Sánchez

Message to reader: Any information on this blog is for informational purposes only. It is not intended in any way to replace professional figures in the medical and consultancy fields.

Messaggio al lettore: Ogni informazione presente in questo blog è puramente a scopo informativo. Non si intende in nessun modo sostituire figure professionali in campo medico e di consulenza.

Consumo de carne y cambio climático: alimentación sostenible con el medio ambiente.

Actualmente el cambio climático es uno de los mayores retos a los que se enfrenta la humanidad. Cada año se emiten toneladas de gases de efecto invernadero a la atmósfera provenientes de la actividad humana. Hay sectores muy poco sostenibles como la industria textil y, entre otros, la industria alimentaria, de la que hablaremos en este articulo.

Dentro de la industria alimentaria podemos destacar diferentes tipos de productos, los de origen vegetal y los de origen animal. Dentro de los productos de origen animal hay distintos sectores como el sector de lácteos, huevos y la industria cárnica. Es esta última una de las mayores contribuyentes al cambio climático.

La industria cárnica está en el punto de mira debido al uso extensivo de la tierra, cada año se talan hectáreas de selva y bosque para dedicarlo a cultivos destinados a alimentación animal y para ganado. Este hecho se puede apreciar muy bien en la selva amazónica, Brasil es uno de los principales exportadores mundiales de carne de vacuno. Cada año se pierden hectáreas de selva para dedicarlas a ganado vacuno o a plantaciones de soja para el ganado. Se calcula que casi el 50% de las tierras fértiles del planeta ya están siendo utilizadas para agricultura y ganadería.

Uno de los mayores problemas a los que se enfrenta la industria cárnica es la cantidad de gases de efecto invernadero que emite. Aunque en cantidad supone un 60% del total de la industria alimentaria, el problema está en el tipo de gases que se emiten. El metano es uno de los gases que más se libera, éste tiene un potencial de calentamiento hasta 80 veces mayor que el del dióxido de carbono en un plazo de 20 años. Para conocer la dimensión del problema, hay que tener en cuenta que una vaca sola produce 100 kg de metano al año.

Sabiendo estos datos, la pregunta es: ¿Qué se puede hacer para llevar una alimentación más sostenible? Actualmente han surgido nuevos tipos de dieta como el flexitarianismo, que consiste en seguir una dieta vegetariana, comiendo carne en determinadas ocasiones. También se puede sustituir la carne por otro tipo de carne menos contaminante, como puede ser el caso de la carne blanca (pollo y pavo).

Se ha visto que reduciendo el consumo de carne o sustituyéndola por otras fuentes de proteína se puede llegar a rebajar la cantidad de emisiones en un 50%. La huella de carbono y la cantidad de tierra fértil requerida para la producción de alimentos de origen vegetal es mucho menor que la de la carne, en concreto, la de la carne de ternera.

Hay una diferencia sustancial entre tipos de carne ya que la carne de vacuno emite hasta 60 kg de CO2 por kg de producto, mientras que para la carne de ave esta cantidad es 10 veces menor. Si comparamos la carne de vacuno con la huella de carbono de los productos de origen vegetal, ésta es hasta 30-40 veces menor. La mayor parte de las emisiones proviene de la utilización del suelo y del mantenimiento del ganado.

Es por este motivo que si estás preocupado por el cambio climático y te gustaría llevar una alimentación más sostenible, el primer alimento que tiene que desaparecer o verse reducido es la carne, en especial la de ternera. Un pequeño cambio en los hábitos alimenticios puede suponer un respiro para el planeta, e incluso una mejora en la salud y en el bienestar personal ya que el consumo excesivo de carne puede ser perjudicial para la salud humana, pero este tema será tratado más adelante.

Escrito por Sara García Sánchez – Graduada en Biología, especializada en alimentación.

Mensaje al lector: El contenido recogido en este blog es de carácter meramente informativo. No se pretende sustituir la labor de los profesionales sanitarios y de asesoramiento científico.

Messaggio al lettore: Ogni informazione presente in questo blog è puramente a scopo informativo. Non si intende in nessun modo sostituire figure professionali in campo medico e di consulenza.

COVID-19 and the evolution of the viruses.

Viruses are small molecules of DNA or RNA covered by a protein structure. They are not fully considered as living beings because when they are outside of the organism they are not alive, they are considered as microscopic parasites that need a host to live. When they colonise an organism they start to replicate itself resulting in multiple copies, while they lose this capacity of replication when they are outside the body. In other words, they need the host to live.

These copies are many times imperfect, there are mistakes in the replication process which lead to mutations. Mutations are the key of the evolution process. These are aleatory changes that could be helpful or harmful for the virus. Helpful mutations make the virus more adapted to the environment, in other words, the virus is more adapted to the host. Those varieties that have helpful mutations can compete better and be more successful than the others, replacing other varieties that are less adapted. Harmful mutations can lead to the infeasibility of the virus.

This success of the viruses can be appreciated by creating a fatality-infectivity ratio. Those viruses that end with the host’s life in a few days are not very successful since the host’s death means the death of the virus, it can not replicate and infect other individuals. The Ebola virus could be a good example, this virus has a fatality rate of 50%, which means that it kills approximately half of the patients. For this reason Ebola outbreaks are well located in the map and short in time. It has no time to spread itself through the population and cross the borders.

On the other hand, viruses like flu or influenza are widely spread around the world. They are very infectious and the fatality rate is minimal. The infected host may have a headache, blocked up nose, low temperature, mild symptoms that allow him to continue with his life, going to work and infecting more individuals. The virus is jumping from a host to another, infecting and living.

It is not necessary to be a prestigious virologist to observe the evolution process of the viruses. COVID-19 is a good example of that. In the first global wave it has a high infectivity rate and a low fatality rate (5-2%), enough to fill the hospitals and to establish an isolation period and close businesses. It has mutated giving place to different varieties, each one more contagious than the previous one. The virus is adapting to be more contagious and less lethal. In the last wave caused by the omicron variety, there is a huge level of cases, whereas the cases of death are minimal.

These facts make us believe that COVID-19 could become a seasonal virus like flu or influenza with many cases and a low number of deaths and the restrictive measures will not be necessary. The “aim” of the virus is to infect and not to kill since it depends on the host to live.

Written by Sara García Sánchez

Message to reader: Any information on this blog is for informational purposes only. It is not intended in any way to replace professional figures in the medical and consultancy fields.

Messaggio al lettore: Ogni informazione presente in questo blog è puramente a scopo informativo. Non si intende in nessun modo sostituire figure professionali in campo medico e di consulenza.

Evolución humana y salud: cómo poblaciones de África, Asia y América se han adaptado a la malaria

Bien es sabido que regiones del mundo como África, Asia y Latinoamérica se caracterizan por tener una alta presencia del mosquito transmisor de la malaria, enfermedad provocada por el género Plasmodium. Es una enfermedad bastante común, a la que estas poblaciones han debido adaptarse.

Para empezar vamos a conocer más sobre la enfermedad. Es provocada por un parásito eucariota llamado Plasmodium, éste sigue un ciclo de vida, que incluye un vector (el mosquito Anopheles), donde se reproduce sexualmente y un huésped (el ser humano), donde se reproduce asexualmente.

Tras la picadura del mosquito el parásito pasa a la sangre. Se transportan hasta el hígado donde se multiplica, teniendo lugar una primera parte del ciclo asexual. En esta etapa el parásito puede reinfectar a los hepatocitos o volver al torrente sanguíneo e infectar a los eritrocitos. En los eritrocitos el parásito se alimenta del contenido proteico, este proceso acaba con la rotura del eritrocito. 

Los síntomas comienzan tras unos 10-15 días desde la picadura del mosquito. La malaria es una enfermedad altamente mortal si no se diagnostica a tiempo, especialmente la causada por la especie P. falciparum, que si no se trata en 24 horas puede convertirse en una enfermedad grave y conducir a la muerte. Se calcula que al año mueren unas 500.000 personas por esta enfermedad.

Sin embargo, hay poblaciones que están desarrollando adaptaciones para convertir a la malaria en una enfermedad menos letal. Se ha visto que hay una prevalencia del grupo sanguíneo 0 en regiones como África, lugar donde la malaria es común. Las personas del grupo sanguíneo 0 están más protegidas contra la malaria grave, mientras que las personas del grupo A son más propensas a padecer una versión grave de la enfermedad y morir.

Se ha visto que la proteína RIFIN juega un papel importante. El parásito secreta esta proteína que se dirige a la superficie de la célula sanguínea actuando como pegamento. Esta proteína se une fuertemente a las células del grupo sanguíneo A, mientras que lo hace débilmente en las células del grupo sanguíneo 0.

Éste podría ser un claro ejemplo de adaptación humana, puesto que en estas áreas geográficas los individuos con grupo sanguíneo 0 habrían resistido mejor la enfermedad, mientras que los individuos con grupo A no habrían sobrevivido, aplicándose así un tipo de selección natural. Esto hace que la prevalencia del grupo 0 cada vez sea mayor, hasta convertirse en el grupo sanguíneo dominante.

Escrito por Sara García Sánchez – Graduada en Biología, especializada en alimentación.

Mensaje al lector: El contenido recogido en este blog es de carácter meramente informativo. No se pretende sustituir la labor de los profesionales sanitarios y de asesoramiento científico.

Messaggio al lettore: Ogni informazione presente in questo blog è puramente a scopo informativo. Non si intende in nessun modo sostituire figure professionali in campo medico e di consulenza.

The benefits of the Mediterranean diet for health

The Mediterranean diet has been developed for years in the countries of the Mediterranean coast like Italy, Spain or Greece. It has been influenced by diverse people like Romans, Arabians, Greeks, pre-Hispanic tribes, bringing more variety to the local cuisine.

This diet is characterized by the use of olive oil, wine, vegetables, fish, cheese, yogurt, fruits, legumes, dried fruits and cereals. It shows the ancient history and traditions of the countries of the region. The use of wine and olive oil was introduced by ancient Greeks and Romans. Then, with the arrival of the Arabians, new food was introduced, such as dried fruits like almonds, legumes like chickpeas and fruits like lemon or orange. After the discovery of America, new food came to Europe, crucial ingredients like potatoes and tomato. For this reason the Mediterranean diet is so varied 

It is well known that this diet has many benefits, it is appreciated by its variety of ingredients and its culinary techniques. It is simple but rich at the same time. There is a predominance of vegetables and fruits, leaving meat in the background. It has always been described as one of the most balanced diets and it is a good example of a healthy lifestyle due to its amount of benefits.

Some of these benefits are the prevention of diabetes and obesity, cardiovascular problems, degenerative illnesses or cancer. It is rich in antioxidants and fiber and poor in saturated fatty acids, it provides a balanced intake of essential unsaturated fatty acids like Omega 3 and Omega 6. 

Photo by Pixabay on Pexels.com

For example, the olive oil, which is widely used for cooking, has a lot of positive effects in our bodies. It helps to reduce the LDL-c cholesterol, which remains in the arteries, it also helps to control the arterial pressure. Another important ingredient, the wine, is characterized by its antioxidant properties and its positive effects on the circulatory system. 

The predominance of wholegrain cereals, vegetables and legumes helps to obtain fiber, which is good for the gastrointestinal tract. There are two types of fiber, the soluble and the insoluble one. The first one helps to regulate blood cholesterol and glucose, it can be found in lentils, carrots, walnuts and apples; the second one stimulates the digestive system helping to combat constipation.

This diet is also rich in dairy products like milk, yogurt and cheese, Italian cheese like mozzarella and Greek yogurt are widely known for their quality. Dairy products help to obtain the necessary calcium, preventing illnesses like osteoporosis, for this reason many experts recommend taking three dairy products per day.

In addition to this, it is low in unhealthy fatty acids and sugar, which is essential to keep a balanced weight. This combined with regular physical exercise could help us to maintain a healthy weight.

In a nutshell, Mediterranean diet is well known for its benefits for health, however it is in danger due to the introduction of fast food, ultra processed food and precooked food. People do not have time for cooking and leave behind more healthy habits. That’s why it is crucial to highlight the importance of Mediterranean diet nowadays, and to invite people to retake it.

Written by Sara García Sánchez

Message to reader: Any information on this blog is for informational purposes only. It is not intended in any way to replace professional figures in the medical and consultancy fields.

Messaggio al lettore: Ogni informazione presente in questo blog è puramente a scopo informativo. Non si intende in nessun modo sostituire figure professionali in campo medico e di consulenza.

Evolución humana, piel y vitamina D

Cuando echamos un vistazo a los diferentes países del mundo según su latitud, vemos que el color de piel varía, de tonos más blancos en el norte a tonos más oscuros en el sur. 

Analizando el clima la respuesta está clara, mientras menos horas de sol y más frío, el color de la piel es más claro; y al contrario, mientras más horas de sol y más calor, la piel es más oscura. Esto se debe a un proceso evolutivo que ha tenido lugar durante millones de años, haciendo que el ser humano se adapte a las condiciones climáticas.

Hay dos presiones selectivas que han hecho que lleguemos a tener esta variedad de tonalidades. La primera, la necesidad de protegerse de los rayos ultravioleta; la segunda, la necesidad de producir vitamina D. 

La primera es bastante evidente, dado que la melanina de la piel es necesaria para protegerse de los efectos dañinos de la radiación ultravioleta. Todos conocemos los efectos nocivos de la sobreexposición al sol. Es por eso que en regiones con muchas horas de sol, como África, la región del sudeste asiático, India o Latinoamérica; la población tiene una tez más oscura. La melanina hace de barrera protectora, ya que sin ésta el cuerpo estaría expuesto a muchos peligros, como el cáncer de piel.

La segunda presión selectiva no es tan conocida como la primera, ya que todo el mundo sabe que el sol en exceso es dañino y tenemos que protegernos. Sin embargo, la producción de vitamina D a través de la piel es más desconocida. Esta síntesis es crucial, ya que pocos alimentos contienen la suficiente cantidad de vitamina D para satisfacer las necesidades del organismo. Por este motivo, en las regiones del norte el objetivo no es protegerse del sol, sino tener la mínima cantidad de melanina para aprovechar las pocas horas de luz y poder sintetizar vitamina D.

Photo by Pixabay on Pexels.com

Cuando nos exponemos al sol, los rayos ultravioleta penetran en las células de la epidermis, donde se encuentra un precursor de la vitamina D, el 7-dehidrocolesterol. Éste se activa con la energía que proporcionan los rayos del sol y se convierte en vitamina D3. Esta vitamina D3 pasa al hígado, donde toma moléculas de oxígeno e hidrógeno convirtiéndose en la 25-hidroxivitamina D. Finalmente este precursor pasa al riñón donde se convierte en vitamina D activada.

Esta vitamina es un nutriente esencial para el organismo, ya que es de vital importancia para el desarrollo de los huesos en la infancia. Entre sus principales funciones están controlar la absorción del calcio y del fósforo en el intestino delgado.

La carencia de vitamina D puede producir enfermedades como el raquitismo, una dolencia que afecta al desarrollo infantil. Hay un rasgo muy característico de esta enfermedad, las piernas arqueadas en los niños. También se caracteriza porque hay una reducción de la fertilidad en las mujeres.

En la edad adulta la carencia de vitamina D afecta a la mineralización de los huesos, provocando más riesgo de fracturas y osteoporosis. El déficit severo conduce a serios problemas como la osteomalacia, que consiste en un reblandecimiento de los huesos. Se da principalmente en personas de la tercera edad, cuando envejecemos los requerimientos de vitamina D aumentan. 

Por estos motivos nuestra piel está adaptada a las condiciones climáticas del lugar. Es por eso que cuando salimos de nuestra zona sufrimos desajustes, por ejemplo, cuando un individuo que vive en latitudes ecuatoriales se va a vivir a latitudes más australes, necesita tomar suplementos medicinales para llegar a la dosis diaria de vitamina D que necesita. 

Sin embargo, hay zonas en las que tienen una piel muy adaptable, como en los países mediterráneos. En esta área geográfica hay muy poca luz en invierno, ya que son noches largas y días cortos con temperaturas muy frías, mientras que en los veranos el periodo diurno es muy largo y hay una gran exposición a los rayos ultravioleta. La selección natural es sabia, y ha hecho que la piel en estas áreas geográficas sea muy plástica, pudiendo perder mucha melanina en invierno y así conseguir la vitamina D que se necesita y adquiriendo una tonalidad oscura en verano para poder protegerse de la radiación. 

El color de la piel tiene un motivo y es uno de los ejemplos más claros en la evolución humana. La selección natural es sabia y sabe buscar soluciones a las presiones a las que la naturaleza nos somete. Sea para protegerse del sol o para obtener vitamina D, hemos ido evolucionando adaptándonos a los cambios, los individuos mejor adaptados han sobrevivido, mientras que aquellos que no estaban adaptados no han podido seguir adelante. Son estos cambios los que nos han hecho llegar a la especie que somos hoy, y gracias a esta adaptación hemos llegado a la diversidad que tenemos hoy en día.

Escrito por Sara García Sánchez – Graduada en Biología, especializada en alimentación.

Mensaje al lector: El contenido recogido en este blog es de carácter meramente informativo. No se pretende sustituir la labor de los profesionales sanitarios y de asesoramiento científico.

Messaggio al lettore: Ogni informazione presente in questo blog è puramente a scopo informativo. Non si intende in nessun modo sostituire figure professionali in campo medico e di consulenza.

Positive mind leads to a healthy body

Mind and body are more connected than we thought. We know when someone is ill, we can appreciate the symptoms, fever, headache, tiredness, sore throat, rash, among others. Our bodies show us different signals that make us think we are sick and we rapidly associate them to an infection provoked by virus, bacteria or fungus. However, it is not always like that, sometimes the origin is in ourselves, in our minds. There is a close connection between mind and body, if we feel mentally sick due to stress, anxiety or depression, our body will respond as well.

Symptoms of a stressed body

Maybe the most common symptom of stress or anxiety is the headache joined to difficulties in concentrating. Everybody has experienced this after a long period of stress. And this is just the tip of the iceberg, there is much more behind these mental pathologies.

To start with an example, when we feel sick, with dizziness, stomach ache, nausea, the first thing that comes to our minds is that maybe we ate spoiled food. However, the connexion between mind and stomach has been always ignored. There is a chronic pathology called “irritable bowel syndrome“, which summarises all these mentioned symptoms. And you may wonder, what is it exactly? The irritable bowel syndrome is a pathology provoked by stress and nervousness, when the person who suffers from this syndrome is stressed, he starts feeling sick, with an extreme urgency of going to the toilet, there are periods of diarrhea and periods of constipation.

Another interesting case of the connection between mind and body. Did you know that there are people allergic to stress? In fact, there are cases of people who have a rash when they are under a long period of stress, just like an allergic reaction. In addition to this, there are other skin pathologies that show up with a stressed mind, such as thrush in the mouth or eczema. 

Moreover, intern effects caused by stress also appear. Depression, anxiety and stress are quite dangerous to our immune system, it has been proved to reduce our defenses making our body more susceptible to illnesses. Didn’t you notice that when you are stressed you catch a cold more easily? Another good example would be the emergence of herpes virus in the lips. There is a huge part of the population infected by herpes virus, the major part does nor realize it because, after the first infection, the virus remains dormant for months or years. After a period of stress the defences of the body drecrease, allowing the activation of the dormant virus. In fact, this is not the only intern effect of stress, it also accelerates the aging process in our bodies.

What can be done?

In a nutshell, our health depends on us, a healthy mind is translated into a healthy body. We have to take care of ourselves and try to reduce the sickly stress that life brings us due to our hectic lifestyle. Work in ourselves is a must, it can be done by working out, practicing our hobbies, taking a day off. Physical exercise is one of the best ways to reduce stress due to the endorphine release. Another advice would be to enhance our social relationships, we should take a break to talk with our workmates in order to be distracted and think less in our problems.

Life is done to enjoy, to laugh and not to be stressed. When we are under a long stress period we are killing ourselves inside. Now the ball is in our court to change our lifestyle to another more relaxed. A healthy mind allows us life more and better.

Written by Sara García Sánchez

Message to reader: Any information on this blog is for informational purposes only. It is not intended in any way to replace professional figures in the medical and consultancy fields.

Messaggio al lettore: Ogni informazione presente in questo blog è puramente a scopo informativo. Non si intende in nessun modo sostituire figure professionali in campo medico e di consulenza.