Transcript Teenage Diets, Nutrition and Wellness

Teenage Diets, Nutrition and Wellness
As Adapted by Dr. Vivian G. Baglien
Teenagers (12-18 years)- Focus Areas
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Nutritional requirements
Dietary recommendations
Macronutrients
Micronutrients
Energy balance
Physical activity
Diet and cognitive ability
Diet and behaviour
Eating disorders
Summary - key issues
Nutritional requirements
• Growth and development are rapid.
• Onset of puberty - characterised by a spurt in
physical growth (height and weight).
• Considerable gain in muscle and bone mass.
• Changes in body composition, e.g. increased
deposition of fat in girls.
• Energy and nutrient requirements at their highest.
A healthy diet is important for
teenagers
Eating a healthy, balanced diet can:
•promote wellbeing by improving mood, energy and selfesteem to help reduce anxiety and stress;
•boost concentration and performance;
•reduce the risk of ill-health now and in the future, e.g.
obesity, heart disease, cancer, and type 2 diabetes;
•increase productivity/attainment and reduce days off
sick.
My Plate
Dietary recommendations
Teenagers should consume a variety of foods from
each of the four main food groups:
Milk and dairy foods (15%)
Bread, rice, potatoes,
pasta and other starchy
foods (33%)
Fruit and
vegetables (33%)
Meat, fish, eggs, beans
and other non-dairy
sources of protein (12%)
Macronutrients
- Average Intakes-
What about dietary fibre?
• Dieticians found average dietary fiber intakes to
be low in teenagers:
- Boys (11-14 years) 11.6 g/day
(15-18 years) 13.3 g/day
- Girls (11–14 years) 10.2 g/day
(15-18 years) 10.6 g/day
• Reference values:
- 15 g/day (11-14 years)
- 18 g/day (15 years or above)
Micronutrients
- percentage of older children and teenagers with
intakes below the RDI (Recommended Daily Intake)
Vitamin
Boys
11-14 yrs
Girls
11-14 yrs
Boys
15-18 yrs
Girls
15-18 yrs
Vitamin A
8%
20%
13%
12%
Riboflavin (B2)
6%
22%
6%
21%
Folate
1%
3%
0%
4%
Micronutrients
- percentage of older children and teenagers with
intakes below the LRNI
Mineral
Boys
11-14 yrs
Girls
11-14 yrs
Boys
15-18 yrs
Girls
15-18 yrs
Iron
3%
44%
3%
48%
Calcium
13%
24%
9%
19%
Magnesium
28%
51%
11%
53%
Potassium
10%
19%
15%
38%
Zinc
14%
37%
9%
10%
What about salt?
• Average salt intakes above recommendations in
teenagers:
- Boys (11-14 years) 6.75 g/day
(15-18 years) 8.25 g/day
- Girls (11-18 years) 5.75 g/day
(excluding salt added in cooking or at the table)
• Recommended maximum daily salt intake:
- 11 years and over: up to 6 g/day.
Teenagers and iron
• Teenagers have increased iron requirements.
• Girls need more iron than boys to replace menstrual
losses (DRI: boys 11.3 g/day, girls 14.8 g/day).
• Low iron intakes (< DRI) in 44% of girls (11-14 years) and
48% of girls (15-18 years).
• 9% of girls (15-18 years) were found to have poor iron
status
• Lack of iron leads to an increased risk of iron deficiency
anaemia and associated health consequences.
• Teenagers who follow a vegetarian diet or restrict food
intake (e.g. to lose weight) particularly at risk.
Iron absorption
• Good sources: meat (especially lean red meat),
liver and offal, green leafy vegetables, pulses
(beans, lentils), dried fruit, nuts and seeds,
bread and fortified breakfast cereals.
• Iron from meat sources is readily absorbed by
the body.
• Vitamin C helps the body to absorb iron from
other sources.
Teenagers and calcium
• Teenagers have high calcium requirements.
• Around 50% of the adult skeleton is formed
during the teenage years (RDI - boys 1000
mg/day, girls 800 mg/day).
• Low calcium intakes (< RDI) found in 24% of 1114 year-old girls and 19% of 15-18 year-old girls.
• A lack of calcium may have consequences for
future bone health e.g. increased risk of
osteoporosis.
Teenagers and energy
balance
• Levels of overweight and obesity are increasing: 35% of
teenagers (12-15 years) are classified as overweight or
obese.
• Teenagers, especially girls, often try to control their
weight by adopting very low energy diets or smoking.
• Restricted diets may lead to nutrient deficiencies and
other health consequences.
• Teenagers of unhealthy weight may need guidance on
lifestyle changes to help them achieve a healthy weight.
Teenagers – physical activity
• Physical activity through life is important for
maintaining energy balance and overall health.
• At least 60 mins of moderate-intensity physical
activity each day is recommended.
• Include activities that improve bone health,
muscle strength and flexibility at least twice per
week.
• 68% of boys and 41% of girls (13-15 year-olds)
Diet and cognitive ability
• Food eaten at school can make up a substantial
proportion of the diet and have a significant effect on
functions such as learning, memory, information
processing and mood.
• Cognition represents a complex multidimensional set
of abilities and cognitive performance is affected by
many influencing factors.
• Nutritional effects are difficult to measure.
Glycaemia
The brain appears to be sensitive to short-term
fluctuations of glucose supply and therefore it
might be beneficial to maintain glycaemia at
adequate levels to optimise cognition.
Eating breakfast
• Starting each day with breakfast will supply
energy to the brain & body.
• Eating breakfast leads to improved energy and
concentration levels throughout the morning.
• Breakfast consumption may improve cognitive
function related to performance in school.
• Other benefits of breakfast include better
nutrient intakes and weight control.
Fluids and hydration
•Even mild dehydration (1-2%) can lead to headaches,
irritability and loss of concentration. This level is not
enough to cause feelings of thirst.
•The recommendation is to drink 6-8 glasses/day (1.2
litres) to prevent dehydration. People need to drink
more when the weather is hot or when they have
been active.
•All drinks count in terms of fluid intake but those
without sugar are best between meals.
Diet and IQ
• Brain health depends on optimal intakes of
nutrients from the diet.
• Much speculation about the importance of long
chain omega-3 fatty acids to behavioural and
cognitive development, including IQ.
• Supplementation studies show the best outcome
observed in children with learning disabilities.
• Current recommendation is one portion of oily
fish (140g) per week.
Diet and mood/behaviour
• There are a number of foods that have a
pharmacological effect in the body which affects mood:
* caffeine;
* vaso-active amines, such as histamine;
* tryptophan and serotonin.
• There is evidence to suggest that poor vitamin and
mineral status may be associated with poor
educational attainment and antisocial behaviour.
Food additives and hyperactivity
• The Southampton study suggested that
consumption of mixes of certain artificial food
colours and the preservative sodium benzoate
could be linked to increased hyperactivity in some
children. The colours are:
sunset yellow FCF (E110)
quinoline yellow (E104)
carmoisine (E122)
allura red (E129)
tartrazine (E102)
ponceau 4R (E124)
Bateman B et al. 2007
• An EU-wide mandatory warning must be put on
any food and drink (except drinks with more than
1.2% alcohol) that contains any of the six colours.
Teenagers - key issues
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Nutritional requirements
Dietary recommendations
Macronutrients
Micronutrients
Energy balance
Physical activity
Diet and cognitive ability
Diet and behaviour
Eating disorders
Teenagers - dietary improvements
needed
• More fruit and vegetables, pulses, wholegrain
foods.
• More milk and diary foods.
• More iron-rich foods.
• More oily fish.
• Less foods high in saturated fat and added sugars.
• Less salt.