From The Desk of Josh Gitalis

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For decades, our culture has delved into what we eat and how the specific foods we choose benefit our health. This is undoubtedly important. Yet let me ask you this: how often do you think about when you eat? And could the ‘when’ be the key to unlocking better health? Let’s dive into the field of chrononutrition – meal timing – and how we can put this health strategy into practice.

What Is Chronobiology?

You’ve likely heard of the circadian rhythm, our bodies’ natural biological clock that runs on a 24-hour cycle. Our circadian rhythm helps to govern our sleep, immunity, hormone release and balance, digestion, our brain function and mental wellness, and far more.

Chronobiology is the field of research that studies our circadian rhythms.

What is Chrononutrition?

Chrononutrition is a newer research sphere that examines how meal timing – when we eat – interacts with our biological clocks and impacts specific areas of health, particularly metabolic health. It also examines what macronutrients we eat at specific times of the day, and how those could be best consumed for optimal wellbeing.

Are you a night owl or a morning person? Chrono-nutrition also looks at chronotypes – your natural inclination for sleeping and waking – and how those affect meal timing, food choices and health. Evidence indicates that later chronotypes (the night owls), who eat late and stay up late, are more likely to have certain risks such as poorer blood sugar control, disordered eating, unhealthy eating behaviours, and higher risk of all-cause mortality.

Chronotypes are partially genetic, but there are still ways we can create routines around eating to improve our meal timing (plus chronotypes can change as we age, enter different stages of life, and make different lifestyle choices).

Health Benefits of Chrononutrition

With all of the existing eating styles available, figuring out what to eat can be a challenge – and adding when to eat certain nutrients can seem like throwing more overwhelming information into the swollen library of health information.

As a health strategy, there are benefits to meal timing and it’s worth considering it as part of your health journey. New research is emerging, in both animals and humans, about how meal timing in particular can benefit metabolic disorders. The advantages of chrononutrition can include:

Improved Glycemic Control

Eating with our circadian rhythm helps our bodies determine when to secrete the specific hormones involved with appetite and blood sugar control such as insulin, cortisol, leptin and ghrelin. Evidence indicates that time-restricted eating, also called time restricting feeding, can improve blood sugar control and insulin resistance, and reduce the risk of developing Type 2 diabetes.

Better Cardiovascular Health

Chrononutrition can help bolster a number of markers of cardiovascular health. Studies show that it can improve blood pressure, cholesterol, triglycerides and hypertension. Chrononutrition helps to lower your risk of diabetes and helps you maintain a healthy weight, both of which contribute to cardiovascular health.

Enhanced Sleep

There are many factors that influence our sleep (you can read about them in-depth here), and sleep is incredibly important to our overall health. Newer research indicates that chrononutrition and strategic meal timing can help enhance sleep duration and quality. It can also promote melatonin secretion, an essential hormone your brain makes to help you sleep.

Gut Microbiome Diversity

The collection of bacteria in our intestines – the gut microbiome – have wide-ranging effects on our health. But our gut bacteria have their own circadian rhythm – plus when and what we eat affects our body clocks. Chrononutrition can contribute to a beneficial diversity of bacteria, which can in turn positively impact our circadian rhythym.

When to Eat – and Optimal Times to Eat Carbs, Fats and Protein

So what does chrononutrition and meal timing look like in actual practice – what should you eat, and when?

Broadly speaking, it’s best to eat earlier in the day and to reduce or eliminate late-night meals and snacking. Eating late at night is associated with poorer glucose metabolism and an increased risk of insulin resistance and diabetes.

Research indicates that it may be better to eat carbohydrate-rich foods in the morning/at breakfast. It could have a protective effect against diabetes, and lead to consuming less carbohydrates later in the day.

Protein and fat can be eaten at breakfast, lunch and dinner (in fact, doing so helps balance blood sugar levels). You may want to be mindful of how much fat you consume at dinner because for some it can take awhile to digest, which can affect sleep. However, if you’re eating an earlier dinner to support your circadian rhythm (say, at 5:00pm or 6:00pm), that may not be an issue.

It’s also important to ensure that your digestion is working optimally – as if it’s not, it’s more difficult to leverage chrononutrition and meal timing.

The Best Times To Take Supplements

Chronobiology can impact when you take your nutritional supplements too. These are my recommendations:

  • B Vitamins: best taken in the morning as they can give some individuals energy
  • Melatonin: in the evening, 30 to 60 minutes before bedtime to encourage healthy sleep
  • 5 HTP: in the evening, to assist with melatonin production, or during the day for mood support
  • Magnesium: can be taken at any time of the day; can benefit sleep if taken in the evening, but if this causes digestive distress then try with dinner
  • Energizing Adaptogens (like rhodiola and ginseng): in the morning
  • Relaxing Adaptogens (like reishi and ashwagandha): in the evening; taking reishi before bed can help prevent nighttime glucose spikes
  • Vitamin D and Fish Oil: Take with a fat-containing meal

Taking any necessary supplements consistently also helps support your body’s natural rhythms. Learn more about strategic supplementation here.

Chronobiology and Drugs

Researchers are delving into how our chronobiology impacts medications and how drug timing can also be optimized. Drug timing varies depending on the medication and condition being treated; it will be interesting to see more on this as the research develops.

Timing Your Exercise

There are contradictory studies about exercise timing and the optimal time of the day to work out. Some recommend working out in the morning, which can help raise testosterone levels, encourage sleep and improve mood (plus you benefit from the increased blood perfusion to the brain for the entire day, and you get it done and out of the way).

Other studies indicate that afternoon workouts, between 2:00pm – 6:00pm when the body’s core temperature is higher, can┬ábolster strength and resistance training. Evening exercise may help improve cardiovascular metrics like blood pressure when compared to morning exercise.

As with diet and supplements, when you exercise will depend on your fitness goals but overall it’s optimal to be consistent with when you do it.

The best exercise, is the one you’ll do. So if you’re not an athlete, just move, and don’t stress too much about the timing (unless it’s right before bed, then you might want to think about a more restorative activity).

Final Word: Consistency Is Key

Chronobiology and chrononutrition are newer areas of study, and we’ll learn more as the research evolves (and more clinical trials are conducted). Creating consistency with nutrition, eating, supplementation, exercise, sleep are important to help support your body’s natural circadian rhythm – so aim to do this as much as you possibly can!