Around three-quarters of children aged 18 months to four years old are overweight due to overfeeding, according to Public Health England. 

The warning comes as the government’s Scientific Advisory Committee on Nutrition (SACN) releases new guidelines on feeding babies.

The report recommends babies are exclusively breastfed for the first six months and are not introduced to solid foods until around six months of age.

Professor Louis Levy, head of nutrition science at PHE, said following this recommendation would help avoid infants becoming “too heavy”.

“Further consideration is needed on ways to monitor overfeeding and overweight prevalence in infants, to help give them the best start in life,” he told the BBC.

The guidelines around feeding babies have been updated for the first time in more than 20 years, but very little of the advice has changed. 

Mothers are still recommended to continue breastfeeding for at least the first year of life once solid foods have been introduced. Cows’ milk should not be given until a child is 12 months old. 

“Breastfeeding has an important role in the development of the infant immune system through the provision of passive specific and non-specific immune factors,” the report says. “There is evidence that not breastfeeding is associated with a higher risk of infant hospital admission for infectious illness.”

Sarah McMullen, head of knowledge at NCT, said: “It’s really important that all parents have access to support and good quality information to help them respond to their to babies’ feeding cues. This matters whether parents are breastfeeding, formula feeding or a combination of both.

“The recommendation remains that solids are introduced at around six months and include a range of foods, flavours and textures.”

The guidelines echo existing advice by the The Royal College of Midwives (RCM), which states exclusive breastfeeding for the first six months of life is “the most appropriate method of infant feeding” but which also acknowledges that a woman’s choice to use formula “must be respected”. 

The new report shows the proportion of women in the UK who breastfeed for one year remains low. Between 32% and 39% of women discontinue breastfeeding before their infant is six weeks old.

From the age of six months, the new PHE guidelines recommend that a wide variety of solids foods, including iron-containing foods, should be introduced in an “age appropriate form”.

The authors say allergenic foods such as peanuts, hen’s eggs, gluten or fish can be introduced from around six months of age and do not need not be differentiated from other solid foods. 

The report stresses that the frequency and amount of sugary food and drinks should be “as low as possible” and states breast milk, infant formula and water should be the only drinks offered after six months of age.