Hypoglycemic Tips Correctly adjusting the "light brightness" can help blood sugar control

Edited by Yimaitong, please do not reprint without authorization
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Introduction: The light/dark cycle of the environment is synchronized with metabolism
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But in modern society, where artificial light is available 24/7, many people are often exposed to bright light during what should be darker hours
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This lighting pattern has a negative effect on metabolism
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This study shows that indoor lighting conditions close to the natural light/dark cycle can help improve glycemic control and increase postprandial energy expenditure
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The aim of the study was to compare the metabolic responses of individuals at risk of metabolic disease under natural light/dark cycles with suboptimal lighting conditions
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The study was published in the journal Diabetologia
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(Scan the QR code at the end of the article to join the endocrine clinical exchange group) Study Design The researchers conducted a randomized controlled crossover trial on 14 overweight adults between the ages of 40 and 75 who met one of the four criteria for insulin resistance.
one
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Also, only participants who went to bed around 11 p.
m.
and slept for 7 to 9 hours were included
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Participants spent two 40-hour periods in the metabolic chamber starting at 6 p.
m.
on day 1 and ending at noon on day 3
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➤ In the first phase (simulating the laws of nature), participants were in bright light from 8:00 am to 6:00 pm, and in a dimly lit environment from 6:00 pm to 11:00 pm
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➤ In the second period (opposite to the laws of nature), at least 4 days apart, participants were in dim light from 8am to 6pm and bright light from 6pm to 11pm
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Subjects wore actigraphy to measure sleep patterns before and during the experiment
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Energy expenditure, sleep metabolic rate, and matrix oxidation were calculated from oxygen consumption and carbon dioxide production
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Skin temperature is measured with a wireless sensor
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Fasting blood samples were collected at 7:45 a.
m.
on days 2 and 3 and at 5:45 p.
m.
on day 2, and postprandial blood samples were taken every 30 minutes after breakfast every day and every 30 minutes after dinner on day 2 (Figure 1)
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Figure 1.
Study Protocol Bright daytime lighting reduces blood sugar.
Participants in Phase II had greater increases in triglycerides after breakfast the next day than participants in Phase I (P=0.
029) (Figure 2d)
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Participants in the first phase had lower pre-dinner blood glucose than those in the second phase (5 mmol/L vs.
5.
2 mmol/L; P=0.
02) (Fig.
2b)
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Figure 2.
Postprandial plasma changes Bright daytime lighting improves energy expenditure Energy expenditure: energy expenditure on the second and third days was not significantly different between the different lighting modes
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There was also no difference in energy expenditure during the postprandial phase of breakfast the next day
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After dinner, participants in the first period had more postprandial energy expenditure than those in the second period
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(Fig.
3a) Sleep Metabolic Rate (SMR): Nocturnal SMR was lower in the second period participants than in the first period (Fig.
3b)
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The respiratory exchange ratio did not differ under different conditions at any time interval
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Figure 3 Energy Expenditure versus SMR Conclusions Bright day-dark night conditions mostly yielded favorable outcomes compared to dim day-bright evening conditions: lower pre-meal blood glucose levels and higher post-meal energy expenditure
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Written by: Yuwen Review: Tian Zige References: [1] Harmsen JF, Wefers J, Doligkeit D.
et al.
The influence of bright and dim light on substrate metabolism, energy expenditure and thermoregulation in insulin-resistant individuals depends on time of day.
Diabetologia (2022).