Author Archives: EllenLee

Can You Live Without Headphones?

When you are studying in the library or walking around the street, you would probably see so many people with headphones. Yes, that is true that Airpods or other types of headphones are getting popular and furthermore becoming one of “the-most-important-belongings” to us. However, did you notice that constant use of headphones can put your ears in danger and might lead to hearing loss? The damage to hair cells in the ears can last temporarily or permanently.


How Headphones Damage Our Ears?

First of all, sound waves need to travel from the outer ear to the inner ear and to be converted into nerve impulses in the inner ear, the cochlea, in order for us to be able to sense hearing. The cochlea is composed of a number of hair cells where sound waves are actually transformed into electrical signals for the brain. Hair cells would be completely bent or broken because of exposure to excessive volume. If the hair cells would not have enough time to recover back, then the damage can be permanent. Therefore, hair cells would not be able to grow back or to send signals to the brain.

Hearing mechanics Credit:

What Leads to Hearing Loss?

Volume and the length of usage likely contribute to hearing loss. Many people might misunderstand that only high volume would damage our ears, however, it just leads to faster damage. Low volume still affects our ears. Furthermore, the impacts of volume and the length of usage on our ears can be equivalent to other noises that audiologists called “noise-induced hearing loss“, a hearing impairment from overexposure to loud music. According to a research conducted by Josef Shargorodsky, the number of adolescents with hearing loss even in mild level had been increasing over time in the United States from 14.9% in 1988-1994 to 19,5% in 2005-2006.

How Should We Protect Our Ears?

In this video, Greta Stamper, an audiologist at Mayo Clinic, suggested some tips to prevent our ears from hearing loss or ear damages.

It is hard to stop using headphones, however, it is possible to protect our ears by having enough recovery time, setting up the volume low or etc.


Ellen Lee

Blog post #2

Let Dark Chocolate Keep Your Blood Vessel Healthy

Have you ever heard having approximately 1-2 ounces of dark chocolate every day is good for our health? Several studies announced that dark chocolate helps to keep our blood vessels healthy. But, do you have any ideas of what makes dark chocolate be beneficial?  Compared to white or milk chocolate, dark chocolate is made of higher contents of cocoa solid in the range of 50 to 90% where the cocoa is known for a rich source of flavonol, a type of flavonoids.

Dark chocolate bars source:


What does flavonoid do to our body?

First of all, flavonoid is a plant nutrient that reduces cardiovascular diseases and can be found in many fruits and vegetables. A type of flavonoids, called flavonol, is found in cocoa and also it is the key source for the benefits of dark chocolate. One of its main function is antioxidants effects. An antioxidant is known for a protector of our body from any harmful damages caused by free radicals and their oxidation. For example, flavonoids lower the amounts of LDL cholesterol, also known as bad cholesterol, in our body since oxidized LDL cholesterol reacts with free radical and cause heart diseases. Another function of flavonoid is that this chemical is used to stimulate cells in inner blood vessels called endothelium. By stimulating the cells, nitric oxide can be produced and used to improve blood flow since nitric oxide can dilate arteries.

The following video explains further details about flavonoid and its function.


Research study on the effects of dark chocolate

A study on flavonoid-rich dark chocolate was done at the University of California. 21 healthy adult subjects were randomly assigned to high-flavonoid or low-flavonoid chocolate for 2 weeks. As a result, The group of intake high-flavonoid chocolate has significant mean changes of 1.3 ± 0.7% in dilation of the brachial artery, the major blood vessel in the upper arm. This study concludes that flavonoid improves endothelium functions and blood flow.


As dark chocolate contains flavonoids more and more, its impacts on our health, especially on cardiovascular health is significant. However, dark chocolate still contains fats and sugars that possibly lead to diabetes or weight increases. 30 to 60g of dark chocolate per day is recommended.



Ellen Lee