New 'Vinegar Diet' Book by 'Eat-to-Lose-Weight' Instructor Who Has Guided Over 3,000 to Success Goes on Sale! Special Campaign Also Announced

KADOKAWA Corporation (Headquarters: Chiyoda-ku, Tokyo; President and CEO: Takeshi Natsuno) will release the health and practical book 'The One-Spoon Instant-Eat Vinegar Diet' (¥1,980, 10% tax incl.) by public health nurse and diet instructor Rie Matsuda on Tuesday, May 26, 2026. Pre-orders at online and physical bookstores begin today, Wednesday, April 1.

©Rie Matsuda 2026

This book, proposed by Ms. Matsuda, who has a reputation for her eat-to-lose-weight methods, is a vinegar diet guide. It focuses on a new habit of effortlessly incorporating vinegar into daily meals, making it easy to practice at the dinner table. The content is designed to be sustainable even for those with busy schedules.

A major feature is that even those who dislike vinegar can easily start. It introduces ways to incorporate it that suppress the strong acidity, along with recipes and eating methods that blend naturally into everyday meals, all structured for easy adoption without special preparation. As the title suggests, its appeal lies in the simplicity of starting with just 'one spoon.' This practical book is aimed at those who want to review their eating habits without overdoing it, making it easy to continue daily.

Additionally, a pre-order campaign has been confirmed before the release. Furthermore, a bookstore purchase campaign and others are scheduled to be implemented sequentially (details to be announced later). Please look forward to 'The One-Spoon Instant-Eat Vinegar Diet' as a new habit starting from your daily dinner table.

Book Purchase Campaign! ・Pre-order Campaign To celebrate the book's release, a campaign will run from Wednesday, April 1, where you can get a special bonus by pre-ordering. For details on how to participate, please see the URL below.

Campaign Period: April 1, 2026 (Wed) 17:00 - May 25, 2026 (Mon) 23:59 How to get the bonus: Follow Rie Matsuda's official LINE and you will receive instructions. URL: https://x.gd/kG50f *Other campaigns, such as the bookstore purchase campaign, will be announced at a later date.

Comment from Rie Matsuda The key to graduating from dieting is being able to continue even on busy days. In this book, I've compiled a simple method to change your body without strain, just by adding 'one spoon of vinegar' to your meals. I would be happy if this helps you graduate from dieting.

©Rie Matsuda 2026

Author Profile Rie Matsuda: Born in 1986. A mother of three. Nurse, public health nurse, and diet instructor. CEO of Belle Lus Co., Ltd., and Representative Director of Belle Life Style Association. After caring for cancer patients as a nurse, she worked as a public health nurse. Through experience in adult health education and providing health guidance to patients with metabolic syndrome and diabetes, she realized that eating habits won't improve unless the person in charge of the dining table acquires knowledge about nutrition and the body. Utilizing her experience of naturally losing 12kg through diet, she started a business as a specialist 'eat-to-lose-weight' diet instructor. She is the author of many books, including 'The Lazy Instant-Eat Diet.'

▶︎X: https://x.com/rie__matsuda ▶︎Instagram: https://www.instagram.com/matsuda_rie8/ ▶︎YouTube: https://www.youtube.com/c/MatsudaRie

Book Information Title: The One-Spoon Instant-Eat Vinegar Diet Price: ¥1,980 (10% tax incl.) Release Date: May 26, 2026 Format: A5 / 4-color Publisher: KADOKAWA Corporation Amazon URL: https://www.amazon.co.jp/dp/4048117408/