What is Chrono-Nutrition? Is it the key to my weight loss ?
Chrono-nutrition or time restricted eating (TRE) is based on two key factors:
1. Having the majority of your food intake early in your day and then reducing the amount you eat throughout the day.
2. Consuming your food in time with your body’s natural sleep-wake cycle or Circadian rhythm. That is only eating during the 8 - 12 hours that your body is naturally awake.
This is not the same as intermittent fasting. Intermittent fasting encourages people to fast for a period of time; sometimes up to a whole day or skip a particular meal, often, breakfast.
The theory behind chrono-nutrition is that the body has a 24-hour circadian rhythm and just like this can be disrupted by shift work and jet lag, it can also be affected by access to energy dense food 24 hours per day. There is increasing research to suggest that the timing of our eating, and not just what and how much we eat may have an impact on our metabolism, and ultimately weight. Not only this but it may also have an influence on our immunity, hormone levels and the likelihood that we will develop chronic diseases such as cancer and heart disease.
Chrono-disruption is common and results from overseas travel, shift work, modern lifestyles, sleep disturbances, excessive energy consultation and irregular times of food consumption.
We have known for a while that sustained exposure to sleep disruption or poor-quality sleep increases the risk of metabolic changes, high blood pressure, weight increase and type 2 diabetes. It is likely that this is due to changes in appetite regulation and the hormones which control appetite and insulin sensitivity.
Our modern lifestyle lends itself to:
frequently being in a postprandial or digestive state
often eating junk food and not meeting the fruit and vegetable recommendations from the National Health and Medical research Council
sitting for long periods after eating rather than being active
eating irregularly or in response to emotions such as sadness or stress
eating most of our calories in the latter part of the day when we are least active.
skipping meals
eating throughout the night as we have such easy access to food.
The theory behind TRE is that you could lose a modest amount of weight and reduce your risk of some chronic diseases by changing the timing of your eating. The primary mechanism by which this would occur would be by reducing insulin resistance and increasing glucose tolerance. The modest amount of weight loss associated with this is independent of any reduction of calories or change in what is consumed at meals.
There are obviously limitations to this way of eating, for example, we would not recommend it for someone who has type 1 diabetes and needs regular insulin and consistent sugar levels or someone with a previous or current eating disorder.
Like any weight loss recommendation, what you eat is only one piece of the puzzle. Other pieces include regular exercise, good quality sleep and stress management.
So, how can you do this?
One way you can do this is by “front-loading.” Plan the day before and make sure that you have a satisfying and well-balanced breakfast to begin the day. Do not let yourself get too hungry throughout the day by eating regularly, well-thought-out snacks. Do not skip meals but breakfast should be your highest protein and calorie meal and dinner your lowest. Aim to have all food intake completed within your 8 – 12 hours of natural wake time.
General Practitioner’s acknowledge the importance of a well-balanced diet in the maintenance of a healthy weight. However, we realise that we are often time poor and deal with multiple issues with our patients at any one visit, which is why when it comes to nutrition, we highly recommend seeing an Accredited Practicing Dietitian. They are the real experts in nutrition and will be able to guide you on this journey and will know a lot more about chrono- nutrition and whether it would be appropriate for you.
Whilst we still need more research into chrono-nutrition and this way of eating can not be recommended for everyone, we do have evidence based research to suggest that TRE can lead to a modest amount of weight loss, may reduce your risk of chronic diseases such as heart disease, diabetes and cancer, improve chances of living longer. Studies have also demonstrated an improvement in sleep quality, and gut microbiome or gut health.
References
1. Franzago, M, Akessandrekku, E, Notarangelo, S, Sttuppia, L & Vitacolonna, E. Chrono-Nutrition: Circadian Rhythm and Personalised Nutrition; The International Journal of Molecular Science: Feb 2023 24 (3)2571. https://www1.racgp.org.au/ajgp/2024/april/is-it-time-to-consider-chrono-nutrition-in-general
2. Devlin, B & Heilbronn, L. Is it time to consider chrono- nutrition in general practice? Australian Journal of General Practice: April 2024 (4): 53; 6971. https://www1.racgp.org.au/ajgp/2024/april/is-it-time-to-consider-chrono-nutrition-in-general
3. Should I try the ‘Circadian Diet?’: The Gut Health Dietitian . https://www.guthealthdietitian.com/blog/circadian%20diet (4/4/2024).