What is the "Borderline" Type of Prediabetes? Explaining Lifestyle Adjustments You Can Start Today!
Hello!
I'm Saori Murakawa, a medical writer.
Are you familiar with the "borderline" type of prediabetes?
The "borderline" type is not diabetes, but a state where blood sugar levels are higher than normal.
Since there is a risk of progressing to diabetes if left untreated, it is important to review your lifestyle habits.
In this article, I will explain
"what the borderline state is," and "what you should be careful about in your daily life to avoid progressing to diabetes."
By reading this article, you will deepen your understanding of the "borderline" type and be able to review your lifestyle habits starting today.
To protect your healthy body, let's start by learning about it!
In another article, we explain the symptoms and diagnosis of diabetes, so if you are concerned about diabetes, please take a look at that as well.
What is the Borderline Type: A State Between Diabetes and Normal
"Borderline" is a state where you are not diagnosed with diabetes, but your blood sugar levels are higher than normal.
"Borderline" has two types: "Impaired Glucose Tolerance (IGT)" and "Impaired Fasting Glucose (IFG)."
Impaired Glucose Tolerance (IGT)
- A state where the 2-hour value of a 75g oral glucose tolerance test (75gOGTT) is 140mg/dL to 199mg/dL
and the fasting blood sugar level is less than 126mg/dL.
In other words, this is a type where
post-meal blood sugar levels are high and difficult to lower.Impaired Fasting Glucose (IFG)
- A state where the fasting blood sugar level is
110mg/dL to 125mg/dL and the 2-hour value of a 75gOGTT is
less than 140mg/dL. In other words, this is a type where
blood sugar levels are high even in a fasting state in the morning.
👉What is 75gOGTT?
A test where you drink a solution containing 75g of glucose after measuring your fasting blood sugar, and then check your blood sugar levels 30 minutes, 1 hour, and 2 hours later.
👉What is fasting blood sugar?
The blood sugar level measured after not eating for 10 hours or more.
It is known that people with the borderline type are more likely to develop diabetes than normal people.
They are also prone to lifestyle-related diseases such as high blood pressure, dyslipidemia, and hyperuricemia, and the possibility of developing diseases such as myocardial infarction and cerebral infarction in the future also increases.
Causes of high blood sugar: Insulin becomes less effective due to poor lifestyle habits
Normally, when you eat, the carbohydrates you consume are digested and absorbed, raising your blood sugar level.
Your pancreas secretes insulin, which works to lower blood sugar levels, upon sensing the rise in blood sugar, returning it to a normal level.
Continued poor lifestyle habits such as overeating and lack of exercise or being in a state of obesity can cause insulin to become less effective, making it difficult for blood sugar levels to drop.
There are also cases where stress is a factor leading to an increase in blood sugar levels.
You can start today! 4 lifestyle adjustments
Because there are no subjective symptoms of being 'borderline,' it is difficult to notice when your blood sugar levels are high.
There is a risk of progressing to diabetes in the future, as well as the potential for complications such as myocardial infarction and cerebral infarction, so it is important to review your lifestyle habits.
You might feel that it is difficult to review your lifestyle habits while leading a busy life with work and family!
For those who feel this way, I will explain lifestyle adjustments you can easily start today.
1. Incorporate dietary adjustments
・Eat slowly and chew well
・Limit yourself to 80% full
・Eat three regular meals a day
・Eat dietary fiber such as vegetables, mushrooms, and seaweed first
・Serve food on small plates
・Reduce or refrain from snacks and alcohol
・When eating out, avoid single-dish meals like rice bowls and choose set meals with more variety and a greater number of ingredients
Eating slowly, chewing well, and being mindful of how you serve your food are recommended to prevent overeating.
This also leads to suppressing rapid spikes in postprandial blood glucose levels.
Consuming dietary fiber can also be expected to have effects such as:
・Moderating the rise in blood glucose levels after meals
・Making it easier to have bowel movements
・Slowing down digestion and absorption after meals
・Suppressing feelings of hunger
These are some of the effects you can expect.
When eating out, it is easy to consume too many calories, salt, sugar, and fats, and to lack vegetables.
It is a good idea to be conscious of choosing items with a well-balanced nutritional profile from the menu whenever possible.
2. Incorporate exercise
When you exercise, sugar is used as an energy source, which lowers blood glucose levels.
It is difficult to exercise while busy every day.
However, even light exercise, if continued over a long period, can be expected to have the effect of improving a state where insulin is less effective.
First, it is recommended to increase energy expenditure through daily activities, in other words, increasing Non-Exercise Activity Thermogenesis (NEAT).
NEAT includes various activities such as maintaining posture, housework, shopping, commuting, and leisure activities, and is considered to account for the majority of energy expenditure through physical activity.
In addition, the Ministry of Health, Labour and Welfare recommends in its physical activity guidelines for health promotion (Active Guide) to move your body 10 minutes more than you do now.
・Use the stairs
・Incorporate walking or cycling into your commute
・Avoid sitting for long periods while working, watching TV, or using your smartphone; stand up and stretch occasionally
・Do stretches or muscle training while watching TV
Let's incorporate these small things into our lives.
3. Incorporate ways to avoid accumulating stress
While it is difficult to eliminate stress completely, let's find ways to release it and refresh ourselves.
・Incorporate light exercise
・Make time for hobbies
・Get enough sleep
・Relax by taking a long bath
・Listen to your favorite music
Please try to find a method that suits you.
4. Create a habit of checking your blood glucose levels
Because there are no subjective symptoms and it is hard to notice, it is important to create opportunities to know your blood glucose levels, such as by having an annual health checkup.
Summary
・Causes of high blood sugar include overeating, lack of exercise, obesity, and stress.
・'Borderline' refers to a state where blood sugar levels are higher than normal, though not yet at the level of diabetes.
・While there is a risk that borderline cases can progress to diabetes if left unmanaged, blood sugar levels can be improved through small, consistent revisions to lifestyle habits such as diet and exercise.
Thank you for reading until the end.
It can be difficult to focus on diet and exercise during busy days, but rather than aiming for big goals or perfection, let's start by incorporating small adjustments!
If you enjoyed this article, your reactions such as likes, comments, or follows would be very encouraging.
In addition to articles explaining diseases, I also write articles about my self-introduction, records of my activities as a writer, and how nurses work, so please feel free to read my other articles as well.
Sources/References
(1) The Japan Diabetes Society (2024) Diabetes Treatment Guide 2024. Bunkodo
(2) The Japan Diabetes Society (2023) Guide to Diabetes Treatment 2023 (Revised 58th Edition, Supplemented). Nankodo
(3) Masato Odawara (2021) Exercise and Body Illustrated: Mechanisms of Diabetes, Metabolism, and Endocrine Systems. Mynavi Publishing
(4) Japan Association for Diabetes Education and Care (2024) Certified Diabetes Educator Guidebook 2024: Learning Objectives and Tasks for Certified Diabetes Educators. Medical Review Co., Ltd.
(5) Ministry of Health, Labour and Welfare. Active Guide - Physical Activity and Exercise Guide for Health Promotion 2023 - (Active Guide 2023) Adult Version. https://www.mhlw.go.jp/content/001361383.pdf (Accessed October 22, 2025)
(6) Ministry of Health, Labour and Welfare. Active Guide - Physical Activity and Exercise Guide for Health Promotion 2023 - (Active Guide 2023) Elderly Version. https://www.mhlw.go.jp/content/001361384.pdf (Accessed October 22, 2025)