And now for you

This is the actual autumn switch. The NHS says everyone, including pregnant and breastfeeding women, should consider taking a daily supplement containing 10 micrograms of vitamin D during the autumn and winter. Labels sometimes give it in IU instead: 1 microgram is 40 IU, so 10 micrograms is 400 IU. Between late March or early April and the end of September, the NHS says you may choose not to take one.

Some adults are advised to take it all year round. The NHS recommends a daily 10 microgram supplement throughout the year for people who are not often outdoors, or who usually wear clothes that cover up most of their skin when outdoors. It also says that if you have dark skin, for example if you have an African, African-Caribbean or south Asian background, you may not make enough vitamin D from sunlight and should consider taking a supplement all year.

Free vitamins with Healthy Start

You might not need to pay for any of this. If you're more than 10 weeks pregnant or have a child under 4, you may be entitled to help through the NHS Healthy Start scheme, and people on the scheme get free Healthy Start vitamins. Its getting vitamins page explains that you can get vitamin tablets while you're pregnant and up until your baby's 1st birthday (they contain folic acid, vitamin C and vitamin D), and vitamin drops for your children from birth until their 4th birthday (they contain vitamins A, C and D). In England and Wales, ask your midwife or health visitor where to collect them, and bring your NHS Healthy Start card. If you're not on the scheme, the NHS says vitamin D supplements, and vitamin drops containing vitamin D for under 5s, are sold at most pharmacies and supermarkets.

Don't double up

More is not better here. The NHS warns that having too much of some vitamins can be harmful. Keep to the dose recommended on the label, and don't give your child 2 supplements at the same time: its example is cod liver oil plus vitamin drops, because cod liver oil also contains vitamins A and D. One supplement on its own is enough, as long as it contains the recommended dose of vitamin D. For reference, the NHS says infants under 12 months should not have more than 25 micrograms (1,000 IU) a day, and adults, including breastfeeding women, should not take more than 100 micrograms (4,000 IU) a day. If your doctor has recommended a different amount, follow their advice.

A handy habit: tie the drops to something that already happens every day, like the first nappy change, so they don't end up in the same mental drawer as the thank-you cards.

Looking ahead to 6 months and beyond

The list grows slightly at 6 months. The government recommends that all children aged 6 months to 5 years are given vitamin supplements containing vitamins A, C and D every day, unless they're having more than 500ml of infant formula a day. From 1 to 4 years, the NHS says children should have a daily supplement containing 10 micrograms of vitamin D.

Who to ask

You don't have to work this out alone. The NHS says your health visitor can give you advice on vitamin drops and tell you where to get them, and a pharmacist can talk you through which supplement would be most suitable for your child. Some products on the shelf contain other vitamins or ingredients, which is another good reason to check.

Getting ready for the colder months? Our guide on how to dress a newborn for autumn covers layers and room temperature, your baby's first cold explains what's normal and when to call 111, and if you're breastfeeding, what breastfeeding actually saves, and what it costs you is an honest look at the sums.

This is general information, not medical advice. Every family is different, so if you have questions about vitamins for you or your baby, speak to your health visitor, midwife, GP or pharmacist. For the full guidance, see the NHS pages on vitamin D and vitamins for children.