Scientifically, we are just beginning to understand how natural light and dark help us to sleep. There are probably many things we don’t yet know. So exposure to natural lighting conditions, where possible, is a good place to start convincing your child’s bodyclock that night time is sleep time.
During the day, take opportunities to go outside with your child. Try to maximise the amount of natural light exposure (without anyone getting burned).
Recent studies have found that it isn’t only the brightness of the light that can confuse the body clock into thinking that night is day, but the colour of the light also affects the body clock. If you need to use artificial lighting at night, keep it dim, warm (red, orange, pink light), and indirect. If you live somewhere where it is light or dark for extended periods, try to keep it light during waking hours, and dark during sleeping hours. Avoid screen-time and bright lights in the hour before bed, and, where possible, avoid using artificial lights at night.
Breast-milk provides natural nucleotides that facilitate sleep and set your child’s body clock to recognise day from night. If you are experiencing extended night wakings, and are trying to avoid unnecessary night feeds, it might be worth making an exception to try to reset your child’s body clock by breastfeeding back to sleep, or to drowsy, at the start of the usual awake period.
There is some controversy over whether you should feed your baby to sleep. For a discussion of the research around this question please see:
Feed your baby to sleep: https://www.practicalresearchparenting.com/2014/08/25/feed-your-baby-to-sleep/
Help your baby to sleep, guilt free: https://www.practicalresearchparenting.com/2014/10/25/10-reasons-why-you-should-help-your-baby-to-sleep-and-not-feel-guilty/
For children who are waking too early in the morning, having an early breakfast may be perpetuating this routine by setting the body-clock to expect food early in the morning. If your child is in the habit of waking and feeding too early in the morning. You could try to gradually shift breakfast time forward until it is at a reasonable hour.
Please add your experiences with these approaches in the comments below. Please provide the age of your child when you tried it. Let us know how long you tried it it for. If it helped, please share the effects you saw. If it didn’t help, why do you think it didn’t work in your case?