Cutting back on calories may help prevent breast cancer. To achieve the best anti-cancer effect, researchers recommend a time-restricted diet in which women only eat at certain times of the day.
To reduce the risk of cancer in the breast, health care providers advise their female patients to enroll in weight loss programs. Usually, they recommend a diet that reduces calorie intake.
However, a newly published study from the University of California (UC) in San Diego suggests that people don’t need to stick to low-calorie foods to reduce weight and avoid cancer. Instead, they would benefit more if they timed their meals in a certain way so that their body can burn more calories.
“Time-restricted eating may be more successful than calorie restriction in controlling the negative effects of obesity, due to the hunger and irritability that makes it more difficult to stick with long-term calorie restriction,” said UC San Diego researcher Dr. Manasi Das.
In a time-restricted diet, an individual may only eat within a specific period each day. Such a diet might deliver more positive effects on metabolism than calorie restriction. (Related: Health benefits of purple carrots.)
Testing the time-restricted diet on obese mice with no ovaries
During the first phase of the experiment, the mice subsisted on a high-fat diet. The obesity-inducing feeding period lasted 10 weeks.
The researchers injected all the animals with breast cancer cells for three weeks. They monitored tumor growth in each rodent periodically.
The researchers permitted some of the mice to get unlimited access to food all day long, while the other animals only received food during the eight-hour-long period at night when they were most active.
The researchers also observed a control group of mice that ate a low-fat diet and were also injected with cancer cells. They compared the results between these animals and the obese mice.
The second phase of the experiment involved mice engineered to develop breast cancer. The researchers separated them into unrestricted diet and time-restricted diet groups as well. All animals received a high-fat diet and were also monitored for tumor growth.
Finally, the third phase examined the role of insulin resistance in the growth of cancer tumors. The researchers inserted an insulin pump in mice and fed them low-fat foods. They compared this group with controls that received a saline solution instead of insulin.
Meanwhile, they administered diazoxide to mice fed a high-fat diet and compared them with a control group that didn’t receive diazoxide.
Time-restricted eating helps prevent tumor growth
The researchers found that obese mice on a time-restricted diet experienced less tumor growth than mice with unlimited access to food. The results also matched the outcomes for lean mice with unrestricted access to low-fat food.
Moreover, the researchers reported that tumors grew faster in mice with increased insulin levels from the insulin pump implant. Meanwhile, tumors in animals treated with insulin-reducing diazoxide grew slower than the tumors in the control animals.
“The results suggest the antitumor effect of time-restricted eating is at least partially due to lowering levels of insulin, suggesting this intervention may be effective in breast cancer prevention and therapy,” concluded the researchers.
“Exploring the ability of time-restricted eating to prevent breast cancer could provide an inexpensive but effective strategy to prevent cancer impacting a wide range of patients and represents a groundbreaking advance in breast cancer research.”