Tag Archives: health

Two’s a Crowd: Liver Disease Risk Increases With Multiple Risk Factors

Posted on October 8, 2018 by | 1 comment

Why It Matters

If you’re a health-conscious sort of person, you probably already know that keeping a healthy diet and living an active lifestyle can reduce your risk of certain health problems – for instance, liver disease. But did you know that exposure to certain chemicals can influence your liver’s health for the worse?

How Tough is Your Liver?

When faced with handling its typical everyday duties, the liver is a very resilient organ. It can easily recover from the early stages of damage that may lead to liver disease, such as having a few drinks in one night. However, when the number of risk factors concerning the liver begins to add up, the likelihood of developing non-alcoholic fatty liver disease increases. Included in the list of risk factors that may pose a threat is the presence of certain chemicals in the environment.

Diagram of the liver in the human body. Source: Wikimedia Commons

 

PCBs: A Potential Threat

Two chemicals that may pose a threat to your liver’s health are vinyl chloride, an industrial chemical, and polychlorinated biphenyl compounds (PCBs), which are oily liquids used in electrical equipment. PCBs have been banned since the 1970s due to their health risks, but unfortunately, they break down very slowly and as a result are oftentimes still present in air, water, and soil sources across the globe. Currently, the greatest potential source for coming into contact with PCBs is through consuming animal products. Recent studies by the Environmental Protection Agency revealed that the maximum concentration of PCBs is just a few parts per billion (ppb) in fish, and even less for meat and dairy. These levels are considered safe for humans, though people who eat large amounts of seafood may be at higher risk.

Structure of a polychlorinated biphenyl compound. Source: OSPAR

 

Healthy Choices Can Reduce Your Risk

However, experts agree that for most people, there’s no need to panic – the effects of these chemicals were only seen to be harmful when combined with additional unhealthy lifestyle factors such as obesity or a diet with a large excess of calories. Just look to rodents for an example: in lab experiments, only the obese mice which were fed excessive amounts of food suffered from the chemicals’ harmful effects, while the healthy mice were not affected by the chemicals. It’s only when faced with additional risk factors, such as obesity, lifestyle, or genetics, that it becomes necessary to pay extra attention to your liver’s health by watching out for the warning signs of liver damage.

https://youtu.be/Rht-1EZc3S0

Video explaining the warning signs of liver damage. Source: Intan Farisha

 

A Final Note

The good news is that for an active person of a healthy weight, these chemicals likely don’t pose a cause for concern. So don’t worry, your liver is probably going to be just fine – as long as you remember to eat your veggies and go for a jog once in a while!

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How do we adapt to high altitude?

Posted on October 1, 2018 by | 1 comment

When I first moved to Canada, my family decided to settle in Calgary. After a couple of weeks, I constantly felt tired and out of breath. I went to a doctor and she said this was symptoms of hypoxia, a high-altitude sickness; the recovery time should be fast since Calgary don’t have an extreme altitude. After a few weeks, the symptoms of hypoxia were gone, but it took a lot longer until I could feel comfortable to join any strenuous exercise.

City of Calgary

A question arose from my experience, why it took me that long to adapt to the high altitude while the symptoms of hypoxia were gone within a few weeks.

The simplest answer is considering this scenario the same as if you catch the flu. The sense of illness could be gone within days; however, full recovery might take up to weeks.

A detailed explanation of high-altitude adaptation involves separating it into third processes and also taken into the consideration of how much above sea level are we talking about.

When we divide the adaptation process into three sections (figure 1), the first part happens right after entering a high-altitude environment. During this period, an individual will experience symptoms of hypoxia and there will be a significant decrease in fitness level. This is a result of low blood oxygen level, which is caused by decreasing air pressure at higher altitude. Since there is less oxygen in the blood, breath rate and heart rate will increase dramatically even during the resting time in order to maintain body basic functions, this will cause overstress on cardiac muscles.

figure 1: The initial response to high altitude exposure. Image retrieve from https://www2.palomar.edu/anthro/adapt/adapt_3.htm

In the second part (figure 2), an acclimatization process would happen, which means the body will make adjustments to stop the decrease in fitness level. To lower the increased cardiac output, our body would produce more red blood cell in capillaries to carry more oxygen, so that the cardiac muscles were less stressed. Failing of acclimatization with low blood oxygen level would cause tissue hypoxia, decreased cardiac output and decreased red-blood-cell concentration. In this case, this individual couldn’t adapt at this altitude and the doctor would suggest moving back to a lower altitude.

figure 2: Acclimatization process. Image retrieve from https://www2.palomar.edu/anthro/adapt/adapt_3.htm

For the third section (figure 3), the result will vary depending on the altitude. With an altitude below 10000ft, physiological adjustment takes time and eventual fitness level will return back to normal. With even higher altitude (above 12000ft), successful acclimatization rarely happens; even if an individual is able to live on the plateau, strenuous exercise and memorization task still remain difficult.

figure 3: Successful acclimatization. image retrieve from https://www2.palomar.edu/anthro/adapt/adapt_3.htm

The failure to adapt to extremely high altitude is not caused by physiological limitation. A study shown for those populations that living on extreme high altitude, shared sections of unique genetic sequence that reduce hypoxia. One of these genes is EPAS1, which is activated by low blood oxygen level and is responsible for lowing hemoglobin concentration in blood for sufficient delivery of oxygen around the body.

The Tibetan Plateau

In addition, physiological adaptation at high altitude increase cardiovascular strength and this characteristic is used to advantage by some endurance athletes.  (figure 4) Altitude training is a several weeks training at intermediate altitude (preferably over 8,000 ft). At intermediate altitude, there is still approximately 20% oxygen, but the partial pressure of oxygen is reduced. The reduction in oxygen partial pressure forces athletes’ body to acclimate to the lack of oxygen, thus producing more hemoglobin and altering muscle metabolism. The increase in hemoglobin concentration and muscle metabolism will give athletes a competitive advantage that lasts up to 10 ~14 days.

figure 4: Increase in fitness after acclimatization. Image retrieve from https://www2.palomar.edu/anthro/adapt/adapt_3.htm

In conclusion, our body is able to make some physiological adaption to the environment until it reaches some limitation. When traveling to higher altitude area, it is important to check your health condition in order to avoid unnecessary damage to your body. Also, a short-term introduction of intermediate altitude is a common training method for the athlete to increase their body condition and gain competitive advantages.

Information attribute from:
Altitude training. (2018, October 14). Retrieved October 21, 2018, from https://en.wikipedia.org/wiki/Altitude_training
Duffin, J. (2014). Faculty of 1000 evaluation for Altitude adaptation in Tibetans caused by introgression of Denisovan-like DNA. F1000 – Post-publication Peer Review of the Biomedical Literature. doi:10.3410/f.718477234.793496726
O’Neil, D. (n.d.). Human Biological Adaptability: Adapting to High Altitude. Retrieved from
https://www2.palomar.edu/anthro/adapt/adapt_3.htm

 

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Posted in Biological Sciences

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Yes, it’s true…you can be allergic to exercise!

“I’m allergic to exercise!!!”

I bet you’ve heard that phrase before or perhaps you even used it to get out of gym class in elementary school!

For the longest time, I thought it was just a figure of speech until last year when my friend was rushed to the hospital after running on the treadmill. In short, I learned that being allergic to exercise is a real condition known as exercise-induced anaphylaxis.

What is exercise-induced anaphylaxis?

Exercise-induced anaphylaxis is rare, affecting only 2% of the population; however, it can be potentially life-threatening. Although, this type of allergic reaction can occur either before or after physical activity, most cases occur after intense exercise, such as running. Nevertheless, don’t count light physical activity out. In fact, exercise-induced anaphylaxis can even occur after gardening!

What are the symptoms?

Although, the severity of exercise-induced anaphylaxis differs among individuals, the most common symptoms include: flushing of the skin, hives, swelling of the lips, abdominal pain, nausea, and vomiting. A combination of several other symptoms, such as swollen tongue, difficulty speaking, swallowing, and breathing, feeling weak, and falling unconscious can also occur in more severe cases. However, this doesn’t mean that you’re allergic to exercise just because your face is beet red and you’re out of breath after a ten-minute run!

Image of hives. Image: Blausen Medical 

How does exercise trigger an allergic reaction?

The process is simple. Imagine the allergen (i.e. exercise) as a foreign invader. Once the invader enters your body, your immune system will produce immunoglobulin E antibodies to protect itself. The foreign invader will then bind to the antibodies causing mast cells to break open and release histamines. Histamines maneuver through your body to fight off the foreign invader and symptoms vary depending on where in the body histamines are released.  For example, mast cells reacting in your nose will cause a runny nose.

Animation of anaphylaxis (0:00-2:32). Video: offworld | design + motion

Do people out grow it?

Exercise-induced anaphylaxis only recently became recognized as a ‘real’ condition. As a result, not many people know about it and more cases still need be studied to determine if it is a long-term condition or not.

If you ever experience a combination of those symptoms listed above, your doctor may recommend an allergy test. Moreover, if you’ve been diagnosed with exercise-induced anaphylaxis but you enjoy exercising, try lowering the intensity of your workout to decrease the chances of having an allergic reaction. Finally, always carry an EpiPen with you and remember “Blue to the sky and orange to the thigh!”

 

 

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Posted on October 1, 2018 by in Biological Sciences

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5 ways to eat eggs bad for your health

Posted on September 30, 2018 by | Leave a comment

Why people need to eat eggs

Eggs are one of the healthiest and the most commonly consumed food in the world. 

They have a high nutritional value because they contain various trace elements and kinds of essential vitamins needed by the human body, such as protein, vitamin D, B vitamins, minerals, and so on. 

 

Recent news about eating eggs

With the improvement of living conditions, people’s requirements on diet have been gradually improved. In today’s society, people are more and more about their health. As part of a balanced diet, people like to eat eggs to supplement nutrition. However, recent news on newspapers shows eats eggs can cause heart disease because of the high protein. Therefore, whether eating eggs bad or good to human health has caused concern.

High protein in eggs

The protein required for people is 0.8g per kilogram of body weight.

According to the dietary reference intake for protein, we can find:

  1. 56g protein required by the average sedentary man per day
  2. 46g protein required by the average sedentary woman per day

One large egg can provide about 6g protein, which makes up over 10% of the average sedentary man required per day and 12.5% of the average sedentary woman required per day.

To prevent side effects of eating eggs, people should pay attention to the following ways of eating eggs.

1. Eating raw eggs

Some people think that if food is cooked, it would lose its nutritional value. Therefore, many people like to eat raw vegetables and seafood, and they think that raw eggs have a higher nutritional value than cooked eggs.

However, eating raw eggs are more likely to carry bacteria, such as coli into the stomach, which can cause gastrointestinal discomfort and Diarrhea. In addition, the raw egg white contains Avidin, which only can be destroyed by high temperature. The Avidin can affect the absorption of the biotin in food, and cause many unpleasant symptoms, such as inappetence, muscle ache, skin inflammation, eyebrow fell off, and so on.

2. Cooking eggs for a long time

Some people think that more time used to cook eggs, it is better for human health. However, it is also wrong because if the egg is cooked for a long time, the ferrous ions in the yolk would combine with the sulfur ions in the egg white to form the insoluble ferrous sulfide, which is difficult to be absorbed. 

Also, fried eggs would be too old and the edges would be scorched when they are cooked for a long time. The polymer-protein in the egg white can form low molecular amino acid, which could form harmful chemicals to human health under high temperature.

3. Eating too many eggs in a day

If people eat too many eggs, the metabolites and the burden on the kidneys would increase, which can cause kidney failure symptoms. 

Here are a few effective tips:

For the elderly people, they can eat 1~2 eggs per day.

For the young and middle-aged people who engage in mental work or light manual labor, they can eat 2 eggs per day.

For people who engage in heavy manual labor, they need to consume more nutrition. So they can eat 2~3 eggs per day.

For young children, they can eat 2~3 eggs per day because of their fast metabolism.

For Pregnant women, lying-in women, breastfeeding women, individuals with weak immune systems and the patient that undertakes postoperative convalescence, they can eat 3 ~ 4 eggs per day because they need to get enough protein.

4. Eating eggs with sugar or soy milk

Many people like to cook eggs with sugar, but eggs can react with sugar under high temperature, and produce a substance called Glycolysis, which can destroy the amino acids in eggs. It is important to note that glycolysis has side effects on blood coagulation, which can harm human health. Therefore, people should leave eggs cool down before adding sugar.

In addition, many people like to have an egg, a bread, and a cup of soy milk for breakfast. In fact, the Trypsin in soy can combine with the egg pine protein in the egg white, which can cause nutrient loss and reduce their nutritional value.

5. Eating excess eggs on an empty stomach

If people consume excessive food with high protein, such as milk, soy milk, eggs and meat, the protein would be conversed forcedly into energy consumption, which cannot provide nutrition to people.

What’s more, when human body accumulates excess protein in a short period, the protein decomposition process can produce a variety of harmful substances that can bad for human health, such as urea, ammonia compounds, and so on.

In brief, if people pay attention to ways to eat eggs, eating eggs can help people meet their demand for protein, and it can bring many advantages to human health.

Information Attribute from:

Denise Hill: https://www.lifehack.org/488728/10-foods-to-eat-and-avoid-on-an-empty-stomach-for-better-digestive-health

Estherjane13: http://www.thewholesomefork.com/2017/02/23/how-many-eggs-is-it-safe-to-eat-per-day/

Haley Hernandez: https://www.click2houston.com/health/is-eating-eggs-good-or-bad-for-you-

Healthline: https://www.healthline.com/nutrition/eating-raw-eggs#section3

Healthline: https://www.healthline.com/nutrition/eating-healthy-eggs

GirlsTalkinSmack: http://women.girlstalkinsmack.com/Food/foods-you-should-not-eat-with-eggs.aspx

Jayne Leonard: https://www.medicalnewstoday.com/articles/323251.php

 

 

Zhou LU

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Posted on September 24, 2018 by | Leave a comment

What are Telomeres?

Telomeres are like the plastic tips at the end of the shoelaces; they are the caps at the end of each strand of DNA and they protect our DNA from becoming damaged.

Telomeres were first distinguished in 1933 by Dr. Barbara McClintock. Recent research lead Dr. Carol Greider, and Dr. Jack Szostak to be awarded the 2009 Nobel Prize in Physiology or Medicine for the discovery of how chromosomes are protected by the enzyme telomerase and telomeres.

Diagram of Chromosome Showing Telomeres in Green Credit: Beauty Black Book

Telomeres Shorten as We Age

Each cell in our bodies replicates DNA and divides. DNA polymerase is the enzyme in charge of DNA replication, but it is incapable of replicating the entire chromosome strand.  Telomeres serve as a “scape goat” of dispensable DNA not needed for vital functions, so when DNA polymerase is ready to fall off the chromosome some of this dispensable DNA is lost.

How Much Telomeres Do We Lose in a Lifetime?

To put it in perspective, we are born with about 11 kb of telomeres, that’s 11,000 base pairs of DNA. By old age, we have approximately 4 kb or 4,000 base pairs.

This significant decrease in telomeres suggests that each cell has a maximum number of cell divisions before it must induce its own cell death. Dr. Leonard Hayflick extensively studied this phenomenon and concluded that each cell can only divide up to 60 times. The maximum number of cell divisions is now known as The Hayflick Limit.

Diagram Showing Decrease of Telomere Length with Age Credit: Defytime

Promising Study on Progeria Cells

Scientist are in hot pursuit to find the fountain of youth. Dr. John Cook and his team conducted an experiment with promising results and with the intentions of helping children with progeria, a rare genetic condition which speeds up aging.

In the study, the participants, aged 1 to 14 years-old, had telomeres lengths of a 69-year-old. Telomeres length was significantly increased in progeria cells as measured by expression of telomerase.

Video on Study on Progeria Cells by Dr. John Cook Credit:  Vimeo

Although this study is very promising, other scientists believe delaying the natural decline of telomere length could be harmful. Dr. Peter Lansdorp from the University of British Columbia explains that telomere shortening is a defense mechanism built within our cells to decrease the chances of developing cancers. Shortening telomere length of cancerous cells causes them to die. Halting this mechanism would allow cancer cells to continue to divide to create tumors.

What Speeds Up and Slows Down Aging?

Studies have shown that following a healthy diet, regular exercise, managing stress, and increase sleep is associated with longer telomeres, whereas higher body mass index, high stress, and smoking are associated with shorter telomeres.

Table of Factors that Affect Telomere Length Credit:  Indian Journal of Medical Research

https://soundcloud.com/sciencetoday/telomere

Podcast on Telomeres as Marker of Aging Credit: US Science Today SOUNDCLOUD

Stress Less Live longer!

Studies suggest that any type of stress will have an effect on your telomeres and will in turn speed-up the aging process. It also shows that taking good care of yourself will  delay the aging process. So next time you feel stressed out, take a second to breath. Your biological clock will thank you.

Video of The Science of Aging Credit: ASAP Science YouTube

Maria-Fernanda Arcila

 

 

 

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The Secret to Speed- Symmetry

What makes fast runners so fast? Sure, strong muscles, hard work, and good technique all contribute to speed- but so does symmetrical knees?

The Proof

Scientists have recently discovered the surprising and remarkable effect symmetric knees have on running efficiency. Robert Trivers, an evolutionary biologist, took a team to Jamaica to investigate if there is any correlation between elite runners and their body symmetry. In one study, the researchers asked the club track and field members to give their best times in their specific running events, such as the 100m dash, 200m, 400m, or 800m. They found that in every single event group the fastest times belonged to the athletes with the most symmetric knees, not with the most muscle mass, lung capacity, or best technique.

Photo by David J. Phillip of Usain Bolt             Source: Oregon Live

 

To further confirm these results, they performed another study in which the research team measured the knee symmetry of 73 elite sprinters, including Olympic gold medalist Shelly-Ann Fraser-Pryce. They compared their measurements with those of 116 local non-runners who were of the same age and sizes as the elite athletes. They found that the sprinters had much more symmetrical knees than the non-runners, concluding that it is indeed a significant contributing factor to running efficiency. “Among the very best sprinters in the world, knee symmetry predicts who’s going to be the best of the best,” Trivers confirms after analyzing these results.

The following is a video of Trivers explaining his study and results.

Source: TEDxUWCCR

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But Why Knee Symmetry?

One reason why knee symmetry could be such a dominant factor in predicting speed is because running is naturally a symmetrical movement, and therefore it will favour symmetrical traits. By not having to compensate for non-symmetric mechanisms, sprinters with knee symmetry are able to save energy and be more efficient in every stride. In addition, numerous studies have confirmed that body symmetry is positively associated with genetic quality and developing advantageous traits, which may also contribute to the correlation between knee symmetry and speed.

What’s Next? 

This study has significant value as the results provide the basis for further research opportunities in the evolutionary biology and sports science fields. Evolutionary biologists may be interested in the genes that develop these symmetrical traits, questioning if they provide any other advantages to humans other than speed.  The track and field community and sports scientists may be curious to explore if there is any way to specifically increase knee symmetry through training in the hopes of it increasing speed significantly.

Furthermore, this finding has prompted more research into this topic and has led Trivers to address further questions, like are runners so symmetric because of good genes or because of the amount of exercise they do? Is it a cause or an effect? Nonetheless, there is a clear correlation between a high degree symmetry and being of the fastest humans. So, if you have symmetrical knees, you might very well be the next Usain Bolt.

By: Olivia Campbell

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Posted on September 23, 2018 by in Biological Sciences

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