If you have erratic eating habits, there’s an app for that. To study the effects of when and where we eat, researchers at the Salk Institute developed an app that allows you to take pictures of what you consume everyday and receive a weekly “feedogram” that shows your daily eating habits.

What they learned from three weeks of data collection from more than 150 people was that most people eat over the course of 15 hours or more each day. They consume less than a fourth of their daily calories before noon; and they eat over a third of their calories after 6 pm.

The context of the pictures spoke volumes.

For many people, there’s no such thing as breakfast, lunch, and dinner. Eating times happen all day long.

The study was designed to learn if reducing the daily duration of eating has an impact on health. The researchers wondered if an eating schedule could prevent “metabolic jetlag” that occurs when our eating patterns are irregular from day to day or from weekday to weekend, causing the body’s metabolism to get out of sync with our circadian rhythms.

A free mobile app was designed that simply required users to send pictures of everything they consumed — food, beverage, water, and supplements. The photos also showed where the food was consumed and what time. Participants for the study were healthy men and women from age 21 to 55 who were not on any type of diet and had not participated in a weight loss program within the past six months.

“One pleasant surprise was how many participants got used to taking a picture of anything they ate or drank; it almost became their second nature,” said researcher Shubhroz Gill, in a statement. “The context of the pictures spoke volumes — for example, when taken next to a keyboard, in bed, watching TV, on the sidewalk, in the car, or while filling gas. This is an example of a new class of research studies that have become possible due to the massive adoption of smartphones.”

The data collected also revealed a snapshot of cultural food practices. Americans drink coffee and milk in the morning, tea throughout the day, and alcohol in the evening. Yogurt is a morning food, burgers and sandwiches are mostly lunch foods, and vegetables and ice cream are eaten in the evening. Starting about 10 in the morning and continuing throughout the day, we eat chocolate and other candy.

The app could also prove to be a tool for personalized medicine. The photos showed that about two-thirds of people took a nutritional supplement or vitamins, though the times they were taken varied from day to day. The same was true for medications.

Another part of the study tested whether the app could benefit people who wanted to eat for fewer hours every day or at more consistent times. Eight participants who were overweight and were used to eating for over 14 hours a day limited their eating to a 10- to 11-hour period for 16 weeks without making any changes to their normal diet. Each of these participants lost 3.5 percent of their weight, and they said they slept better and had more energy.

“The study is about developing methods and offers some preliminary insight into what and when people eat,” according to researcher Satchidananda Panda. “One should not take away the message that changing the eating duration is the only method to improve health. This may also be risky for individuals with undiagnosed fasting hypoglycemia.”

To get a better picture of people’s eating behaviors and study how socioeconomic conditions could vary the results, the researchers intend to collect data from shift workers and people in various socioeconomic groups. They also hope to study the benefits of restricting eating time under different conditions of activity, sleep, and disease.

If you would like to contribute your intake data to the Salk Institute study, visit http://mycircadianclock.mycircadianclock.org/ and download the app "myCircadianclock" from the iOS App Store or Google Play. After two weeks of recording your intake of food, water, other beverages, and supplements, your own “feedogram” will be revealed.

The study is published in Cell Metabolism.