Infant feeding and obesity and CVD risk

Question 1

Define infant programming

Answer 1

Infant programming is the idea that there is a critical period in an infants life which has long-term effects. This can be mediated by programming stimuli which may be endogeneous (hormones) or environmental (nutrition)

Question 2

Define the ‘ideal plane of nutrition’ for an infant

Answer 2

This is the idea that in the critical window for nutrition over-feeding could result in later obesity and CVD risk, and under-feeding in this time could lead to long-term stunting of growth

Question 3

What is the idea of ‘delayed appearance’ in the context of infant nutrition programming?

Answer 3

This is where alterations to nutritional status to an infant may not have apparent health effects until later in life. For example, over-feeding as a baby may not lead to an overweight child, but the person may become obese in adolescence

Question 4

Breastfeeding and CVD risk: blood pressure

Answer 4

• The LANCET review found no association between breastfeeding and blood pressure
• The PRETERM study found that the breastfed infants had lower blood pressure
• PROHIBIT study found no difference in blood pressure outcomes at 6 and 11.5 year follow-up
• in adults, the Framingham study found that a 2 mmHg drop in BP leads to a reduction in hypertension by 15%, CHD by 6% and stroke by 15%

Question 5

Breastfeeding and CVD risk: blood lipids

Answer 5

• LANCET review found no association between breastfeeding and improved blood lipids
• PRETERM trial found better HDL and lower LDL levels in breastfed infants
• In adults, a 10% reduction in cholesterol is associated with a 25% reduction in CVD, and reduction in CVD mortality by 13-14%

Question 6

Breastfeeding and overweight/obesity risk (including the ‘growth acceleration hypothesis’)

Answer 6

• LANCET review found reduced risk of overweight/obesity in breastfed infants
• PROHIBIT study found that there was not increased risk of overweight/obesity at 6 and 11.5 years. But at 16 years the breastfed infants actually had an increased risk of obesity
• growth acceleration hypothesis: idea that if a baby has a growth spurt this is associated with greater obesity risk later on. This is independent of bottle or breastfeeding. Epidemiological evidence provides support for this
• the most important factors for infant weight gain is bottle feeding (this means that often forced to finish, regardless of the contents, which may mean ignoring satiety cues), and responsive feeding from the parent
• baby-led weaning does not reduce the risk for overweight/obesity, although does increase infant enjoyment of food and reduces fussiness. Big question over how much nutrition they are getting, though

Question 7

Implications for practice: what do we recommend for preterm or term infants?

Answer 7

• preterm infants: need to be mindful about reduced nutrition in critical period reducing survival and neurocognitive outcomes. Although over-feeding could result in later CVD risk, need to push nutrition as much as possible
• for term infants, should not push nutrition too hard as could lead to rapdi weight gain and later CVD risk
• formulas should be reformulated to be lower protein and breastfeeding promoted where possible