Are you eating a low carb diet or going full blown Keto? Both ways of eating focus on higher fat and protein foods and cut down heavily on carbs. You might be one of the rare types who genuinely enjoy eating this way naturally, but usually they’re undertaken for a reason. Weight loss, improved mental focus and reduced cravings are some of the popular attractions of keeping your carbs at bay.
If you’re doing either you may know that carbs should still be woven into your diet. After all, what’s life without our satisfying, starchy friends?
Reasons to eat higher carb meals might be to improve your mood, give a feeling of higher satiety or just to break the exhausting cycle of restriction. The classic ‘meat and two veg’ formula can get a bit tiresome after a while!
Let me pause for a moment to state the obvious. Of course, when I’m talking about a higher carb meal, I’m referring to root vegetables and whole grains rather than processed foods, flours or confectionary! Although these are necessary for a balanced and happy lifestyle, I’ll lay off recommending them in this blog article. Maybe another time, as I’m more than partial to a sweet little something every now and again.
Anyway, let’s continue!
Whether you eat higher carb meals, days, weeks or months, you should have a system that works for you and your own body. And, whichever way you’re doing it, you might wonder when would be the best time of day to eat a higher carb meal. So…..
Are carbs in the morning best for your health or are evening starches your better bet?
This is a common question, but one that has not been easily answered yet. And there’s good reason. The research is grey and there’re strong arguments for both sides of the coin.
Before you read on you should know that there’re compelling arguments for both sides and so I’ll be providing no definitive answers today. Instead, as easy as it sounds, you should do what suits YOU and that which supports your mood, energy, digestion and sleep quality the best.
Click this image to watch my video explanation or please read on to help you decide what would work for you.
Nighttime Carbs
The main reason you might want to eat carbs in the evening is for a deep and peaceful slumber.
Carbohydrate foods increase blood levels of an amino acid called Tryptophan (1) – the precursor for melatonin production. Just to remind you, melatonin is the hormone responsible for those blissful zzzzzz’s.
But would eating a higher carb dinner REALLY improve your sleep?
The facts are shaky. But a study showed how its willing adult participants’ melatonin levels REDUCED after a 2-7 day fast and who were therefore severely carb depleted. However, after a quick fix of a glucose supplement their melatonin levels normalised again (2). Could this suggest that carbohydrates help to keep melatonin levels regulated and therefore improve sleep? It’s an unsubstantiated theory with little solid evidence, but you can see the sense.
In fact the biggest regulator of melatonin production is light and age (decreases with age) and therefore the details of your diet has a lot less to do with it. However, there’re exceptions. There are foods and drinks that can definitely hinder your sleep quality. As you know caffeine will send most of us on a rollercoaster rather than induce a dreamy visit to lala-land because caffeine blocks the function of melatonin (2). Also a diet high in processed sugars and refined carbohydrates can stop your ability to fall into a deep sleep (3).
So certain things we eat can stop us from sleeping. But can carbs in the evening or even eating certain foods lead to a good sleep? Foods containing naturally high levels of melatonin include tomatoes, rice, walnuts, strawberries, olive oil and wine. But, even though I’d love it to be true that eating certain foods can instantly boost melatonin, it’s actually not the case – the regulatory system of melatonin secretion is a lot more complex than that!
So, are there any other reasons to eat your starches in the evening?
Yes! You should consider that eating carbs in the morning could trigger further carb cravings during the day leading to possible weight gain. If you’re a person who ‘once you start you can’t stop’, then carbs in the evening might be your best bet.
Morning Carbs
Following an overnight fast, you’ll break it with your first meal of the day – break-fast. Enter carbs!
When in a fasted state our cells naturally become more insulin sensitive meaning that they’re more accepting of glucose for energy. So wouldn’t it make sense to eat those macro’s in the morning?
Insulin sensitivity for an average person is highest in the morning and gradually decreases as the day progresses with it reaching its lowest level in the evening (4). This would mean you’re less likely to store carbs as fat during this time. Therefore if weight loss is your goal then this might suggest you’re better off eating carbs in the morning while your cells are able to take them in more easily for energy.
Even more interestingly the variation for insulin resistance is so wide that an average adult could have normal tolerance to carbs in the morning but be as resistant as a pre-diabetic by the nighttime! (5). This is pretty mind-blowing and would be a strong case to leave off the carbs in the evening.
So could chronic nighttime eating put someone at higher risk of weight gain or even diabetes?
Admittedly, this depends on the extent to which the person has been fasted (6,5). For example if you were to eat very low carb during the day your insulin sensitivity will still be high in the evening.
This spills over into which meal should be the largest of the day. Due to improved glucose tolerance and naturally better insulin secretion, breakfast should even be the largest meal of the day, as well as the highest in carbs.
There is one more reason to eat carbs in the morning.
The hormone leptin (your satiety hormone) rises the most after eating carbs when compared to fat (7) and so this might mean better postprandial satisfaction and therefore better management of your food intake during the day.
What About Exercise?
You may be wondering if you should fuel up with carbs around the time that you hit the gym. This wouldn’t be a bad idea at all, and in fact might help your physical performance.
Endurance and low intensity training such as a dance class or a gentle swim needn’t have the support of carbs. Your fat stores and ketone levels can do a splendid job of producing an excellent session. You can even lift heavy weight and not lose your strength. But on the other hand if you like to train like an animal and enjoy exercise such as CrossFit, power lifting or HIIT, you might want to pop those potatoes!
This is because your body uses glycogen from carbs, at higher levels of intensity and in fact using fat or ketones for energy has been shown to not improve your level of fitness and can even decrease your time to exhaustion, especially in females (8). So if you’re an athlete or if performance and personal bests are important to you, then increase carbs around your training.
In fact many people on a full blown Keto Diet report that higher intensity activities are harder without carbs. So, if you feel the same, it would be good to eat your carb dense foods before or after training to replace the glycogen deficit created in your muscles.
Insulin sensitivity is increased during and shortly after exercise which is good news for carbs! In fact an interesting study noted that insulin sensitivity increased by 25% after participants jogged for 90 minutes (9) – that’s quite an increase! For this same reason if you’re looking to increase your muscle mass you may also need to up your carb intake before or after training as low carb diets have been found to retain muscle mass well, but fall short of adding mass (10).
So Which Do You Prefer?
As you can see there are good points made for eating carbs in the evening, morning, and even around exercise.
As I said at the start of this article, given this information, it’s best to follow your own instincts and eat your carbs at a time that suits you. Be mindful of your mood, your energy levels and sleep quality and use these insights to decide which is best for you.
References
1. Markus, C.R. (2007). ‘Effects of carbohydrates on brain tryptophan availability and stress performance’, Biological Psychology, 76(1-2), pp.83-90.
2. Peuhkuri, K. et al. (2012). ‘Dietary factors and fluctuating levels of melatonin’, Food and Nutrition Research, 56.
3. St-Onge, M.P. et al. (2016). ‘Effects of diet on sleep quality’, Advances in Nutrition, 7(5), pp.938-949.
4. Campioni, M. (2005). ‘Morning to evening decrease in insulin sensitivity and beta-cell responsivity to identical meals, Metabolism, Abstract only.
5. Poggiogalle, E. Et al. (2018). ‘Circadian regulation of glucose, lipid and energy metabolism in humans’, Metabolism, 84, pp.11-27.
6. Dashti, H.S. et al. (2019). ‘Decreased orla glucose tolerance and insulin response during biological evening versus morning among adults under free-living conditions’, Sleep, 42(1), pp.18-19. Abstract only.
7. Romon, M. et al. (1999). ’Leptin response to carbohydrate or fat meal and association with subsequent satiety and energy intake’, American Journal of Physiology, 277(5), pp.55-61. Abstract only.
8. Harvey, K.L. et al. (2019). ‘Ketogenic diets and exercise performance’, Nutrients, 11(10), pp.2296.
9. Taylor, H.L. et al. (2018). ‘Post-exercise carbohydrate energy replacement attenuates insulin sensitivity and glucose tolerance the following morning in healthy adults’, Nutrients, 10(2), pp.123.
10. Vargas, S. (2018). ‘Efficacy of ketogenic diet on body composition during resistance training in trained men: a randomised controlled trial’, Journal of the International Society of Sports Nutrition, 15, pp.31.
