Sleep Experts Weigh In: The Impact of Increased Time at Home on Sleep

Satoru Tsubota
M.D., Ph.D., Associate Director of Amabare Clinic.
While practicing medicine, Dr. Tsubota focuses on prevention and improving sleep quality under the concept of "living a healthy life through good sleep." He disseminates sleep-related information through various media, including the internet, television, and magazines.


Commentary
“Adequate exposure to bright light during the day stimulates the production of serotonin in the brain. Serotonin is then converted into melatonin, known as the sleep hormone, at night. Spending time in dim environments during the day leads to insufficient serotonin and melatonin, making it difficult to sleep soundly. Physical activity promotes deeper sleep as the body works to recover from fatigue. Lack of movement means the body doesn't get tired, making deep sleep less likely. While melatonin increases at night, exposure to bright light or blue light reduces melatonin levels and diminishes sleepiness. Electronic devices like TVs, computers, gaming consoles, and smartphones emit significant amounts of blue light. Prolonged use of these devices late at night can lead to difficulty falling asleep and reduced sleep quality.”


Your Bedding Might Need an Upgrade! A Sleep Expert's Checklist
According to Dr. Tsubota, mattresses that are too firm can cause pain at pressure points, disrupting sleep. Conversely, mattresses that are too soft can cause the body to sink in, hindering movement and sleep quality, potentially leading to body aches or stiffness. Furthermore, as mattresses age and their materials degrade, the lumbar area can sag, causing back pain and impeding sleep quality by restricting movement. Poorly maintained mattresses can also become breeding grounds for mold and dust mites, contributing to asthma and allergies. Therefore, re-evaluating your current mattress is an effective step towards achieving restful sleep.

Checklist: Is Your Current Mattress Suitable for Your Body?
If you check any of the following, it may be time to reconsider your mattress:
□ You experience pain or stiffness in any part of your body when lying on your back.
□ You find it difficult to breathe smoothly.
□ When lying on your side, the line from your face's center to your chest/abdomen's center, and the line between your legs are not parallel to the floor, with some areas lifting off.
□ You are unable to perform smooth, integrated rolling movements from your upper to lower body.

Upgrade Your Sleep with a Mattress Topper

A mattress topper is a supplementary bedding item used in conjunction with a mattress. It is typically placed on top of a mattress that has become worn or uncomfortable. For those hesitant to discard their current mattress or face the hassle of replacing it, a topper offers a simple way to enhance sleep quality. It can also serve as a futon substitute and be stored compactly, making it a highly functional and convenient item.


Product Lineup
ZINUS Mattress Topper 5 cm TorsoTec - ¥5,130 (Amazon price)
Recommended for first-time mattress topper buyers. This two-layer structure features foam infused with green tea extract and pressure-relieving foam. It prevents excessive sinking from the waist to the hips, making it ideal for those whose back pain worsens during sleep.

ZINUS Memory Foam Mattress Topper 10cm Green Tea - ¥7,388 (Amazon price)
The upper layer is memory foam that conforms to the body in any position, while the lower layer is high-density foam that provides balanced support. Its firm memory foam feel makes it suitable for those who found previous memory foam mattresses too soft. The 10cm thickness allows it to be used as a standalone mattress as well as a topper.

ZINUS Memory Foam Mattress Topper 5cm Cooling Gel Infused - ¥6,449 (Amazon price)
Ideal for those whose sleep is disturbed by heat or who change sleeping locations seasonally. Its portability and cooling properties ensure a comfortable night's sleep. The memory foam offers a gentle, enveloping feel, perfect for those who prefer a plush sleeping experience.

ZINUS Memory Foam Convoluted Swirl Mattress Topper 5cm - ¥5,776 (Amazon price)
Surprisingly lightweight, this topper is convenient for those who need to move their mattress. It's recommended for individuals looking to try a mattress topper while using their current mattress or for those who prioritize cushioning.