There is an increasing amount of research to suggest that there may be better times to eat for health, performance and body composition.
In this article I’ll share four key recommendations regarding timing your nutrition that I have found to be worth considering, based on scientific research and helping clients achieve their goals.
Meal timing myths
Before we move onto the recommendations, let’s cover the various inaccurate messages that you have likely been subjected to about meal timing – some of which may include:
Whilst such statements are inaccurate, this doesn’t mean that meal timing does not play an important role in our health both directly and indirectly through our choices. For example, the timing of when we eat impacts our broader eating, activity and sleep habits.
When we eat also impacts our circadian rhythm which impacts our health. And our circadian rhythm impacts the effects of the meal we consume which impacts our health – to find out more about this check out Why meal timing matters (part 1): what is a circadian rhythm and why is it important?
Recommendation 1: choose your feeding window
Just like you have hours that you work within, choose set hours that you eat within. I like to focus on the hours that you can eat versus hours that you fast – same effect on physiology but different impact on thinking whereby you are coming from a place of abundance.
If you read part 1 you’ll be aware that processes within biology run in a cyclical manner – wake/sleep, activity/rest, light/dark. Feeding/fasting is another one of these. Certain processes can only occur when you are not eating food, for instance the repair and growth of the gut lining.
Creating an intentional eating window is likely to result in become more intentional eating habits. This is likely to be beneficial – unless it becomes an unhealthy focus of course. For anyone who wants to lose fat, the time within which you eat food can be a tool for controlling calorie intake. A 10-week study on overweight individuals showed that a restricted feeding window (3 hours less) resulted in decreased calorie intake, weight loss and improved blood sugar management (3).
Many other studies show time restricted feeding to aid weight loss (4). I think it is important to note that the feeding window doesn’t need to be extreme – my advice is to begin with eating within a 12 hour window and then see if you find it beneficial to move to a 10, or potentially 8 hour feeding window.
The optimal time for eating within will depend upon you, your body composition, lifestyle and goals. For example with clients who are athletic, have a higher calorie intake, are more active, or trying to gain weight/muscle etc, a feeding window close to 12 hours is more appropriate. This article here on nutrient timing is more relevant for optimising food intake for performance and recovery.
Many females do better with a longer feeding window because fasting is a stressor, it can negatively impact hormone health and may be associated with irregular and absent periods. Research indicates that females may also do better with fat loss results when they go into exercise fed versus fasted.
Additionally, if a client wants to lose weight and finds that eating within a 12 hour time frame works for them assists them with adhering to their calorie deficit, then there would be no reason from my perspective to change this. The purpose is simply to establish a set period of time where you are consuming food and establish this time frame according to when is best for you.
Recommendation 2: have a schedule
Research suggests that eating at consistent times may benefit weight management and blood sugar regulation (1). Hunger/fullness hormones and insulin sensitivity have a circadian rhythm. Therefore eating at certain times may be more beneficial according to your circadian rhythm but also eating at consistent times will regulate the activity of those hormones in line with your eating schedule so that you can better manage hunger levels.
Eating at inconsistent times is associated with being at a higher bodyweight and switching from an irregular meal pattern to regular daily meal pattern may increase your total calorie burn by 5% (2). This is indicated to be due to the thermic effect of food (TEF) which is the amount of calories that you burn to digest, metabolise and absorb the meal you’ve eaten. The TEF appears to be higher when you have a consistent eating schedule versus an erratic eating schedule.
Having an eating schedule provides the foundations for planning your nutrition intake which is critical for creating any change. Becoming aware of your calorie intake throughout the day is necessary to lose fat, maintain a healthy weight and gain muscle. Even if you do not wish to fully plan your nutrition, having an eating schedule puts you in a stronger place to put a loose framework around what and how much you are eating at those times. This makes reaching your body composition goals a possibility.
Having an eating schedule also means that you become more aware of what you are eating – for example, ensuring that you have protein throughout the day. Effectively distributing calories and protein throughout the day are the fundamentals for having consistent energy, being healthy and performing at your best.
Lastly, following an eating schedule means that you are more likely to create the time to eat and therefore be present whilst eating your meal and eat in an undistracted manner. The impact that being present has on food choices, food volume consumption and how you feel physically and mentally from the meal is understated.
Recommendation 3: choose the best time to eat
As discussed in part 1 aligning our circadian rhythm with day/night is associated with better physical and mental health and wellbeing. The metabolic response to consuming a meal, aka blood sugar and fat management becomes less effective when this occurs in closer proximity to when we are sleeping versus in the morning (5). Obviously the degree to the significance of this for you depends upon your health and activity status.
If you are reading this and are in poor metabolic health, e.g. have poor blood sugar management then you may be able to make improvements to your health by finishing your food intake further away from bedtime since you are less insulin sensitive in the evenings due to the circadian rhythmicity of insulin levels (7).
For most of you who are reading this and are healthy metabolically and train regularly, this won’t apply to you – you will be insulin sensitive and require nutrition and calories over a greater period of time, i.e snacks closer to bedtime. For performance, recovery and health. Additionally, if you add evening training into the equation, then again, evening calories and nutrition to support this are pertinent.
Whilst there is an association with eating closer to bed and increased body weight (6) I would note that this relationship is not causal and the likelihood is that eating late at night for many people is associated with making poorer food choices and therefore eating more calories. Therefore for you who is reading this, this likely does not apply to you since I imagine that your eating before bed is a snack that supports you to meet your calorie and protein needs – and facilitates recovery and muscle growth.
Whilst there may be benefits to eating more calories in accordance with daylight, this doesn’t mean that eating as soon as you wake up is optimal when cortisol levels will be peaking and blood sugar levels will likely also be higher. Some research does indicate that having a “breakfast” improves blood sugar management throughout the rest of the day, however this is variable and may be learned, as this didn’t occur for individuals who routinely skipped breakfast (8).
Obviously if you are training soon after you wake, then timing your nutrition to support this is critical. Some research indicates that having more calories earlier on in the day may lead to a greater amount of calories being burned throughout the day (9). However unless this cancels out the amount of calories consumed in those hours, weight loss will not occur!
Recommendation 4: calorie distribution
Since calories are the fuel for generating energy to fuel everything you do, I tend to recommend distributing them relatively evenly throughout the day. Additionally since energy is used to digest and absorb a meal, a larger meal may result in you feeling tired. Therefore having meals/snacks with a calorie amount that is not overly big for you and eating more frequent meals can help mitigate this and improve energy levels.
For weight loss, research indicates consuming more of your calories earlier on in the day is associated with having less calories overall as well as better blood sugar management and lower levels of hunger (10, 11). I would argue that whether you consume less calories overall will depend upon the underlying drivers of your eating habits.
However for anyone with poor blood sugar management consuming more calories earlier on in the day is likely favourable. Again if you train regularly and if you train in the evening then this is not going to be relevant to you!