Introduction

Adolescence is a time of transition and change and of greater and increasing independence. During this important period of development, a healthy, varied diet is important to ensure that a nutrient dense diet is achieved to support learning and growth. Additionally, due to increased autonomy it is essential that young people are supported to feel educated and empowered regarding food choices and positive lifestyle habits, to support them during this life stage. The long term implications of poor nutrition, and negative lifestyle choices, such as alcohol abuse, smoking and drug experimentation, as well as the increased prevalence of mental health conditions during this life stage, should also be articulated, so that young people feel equipped and empowered early on to get help and support, should they experience health challenges. 

Key Risk Factors

Increased Risk of Psychological Disorder Development

Adolescence is a time of increased susceptibility to mental health problems, and a lifestage where mental illnesses such as depression, anxiety, eating disorders, substance abuse disorders and psychosis may begin to develop. Moreover, schizophrenia and personality disorders may also begin to develop during adolescence. Globally, 1 in 7 10-19 year olds develop a mental health condition, and suicide is the fourth leading cause of death in 15-19 year olds.  Key risk factors for the development of mental health conditions during adolescence include stress, the influence of media, lower socioeconomic status, and experiencing bullying and witnessing and experiencing violence and abuse in the home. Experiencing parental divorce, chronic illness, teenage pregnancy, and living with autism or additional learning needs may also further increase the risk of developing a mental health condition. Indiviuals from ethnic minorities or identifying as a part of the LGBTQIA+ community have also been identified to be at increased risk of being diagnosed with a mental health challenges due to experiencing discrimination. In terms of modifiable lifestyle factors, diet quality has been observed to be a key determinant of psychological wellbeing in 12 and 13 year olds.  Research has additionally indicated that adolescents who experienced sleep issues during childhood, were at higher risk of developing mental health conditions during adolescence.  Moreover, increased screen time and sedentary lifestyle has also been identified as a risk factor for increased symptoms of depression in adolescents. 

Inadequate Sleep

Inadequate sleep duration is prevalent among adolescents. Sleep disruptions amongst adolescents may occur due to consumption of energy drinks and other unhealthy food and drink choices, increased exposure to screens, and not going to bed early enough.. 

Increased Independence Regarding Food Choice 

Adolescence is a time of increased independence regarding food and drink choices for many teenagers. Research has indicated that this demographic has higher intakes of cakes/cookies/pastries, sugar and sugary drinks and salty snacks. This may have a negative impact on brain development and health due to the pivotal role that nutrition place during this crucial period.

Social influences on eating are powerful and pervasive, because other people have such an
influence on our eating is that they provide a guide or norm for appropriate behaviour. Social
norms and peer pressure are a powerful influence on behaviour, because following (or not following) norms is associated with social judgements. Research has shown that this need to belong with regards to food consumption and peer influence has an impact on vegetable and fruit consumption in adolescents. Despite increasing independence during this life stage, it is important that adolescents still share meals regularly with their families, if possible, as research has indicated that higher incidence of shared family meals may be associated with better diet quality, and higher consumption of vegetables and fruit for adolescents. 

Experimentation with Alcohol, Tobacco, Drugs and Other Substances

Some individuals may begin to experiment with alcohol, tobacco, vaping and drugs during adolescence. Binge drinking in teenagers has been associated with negative effects on brain development during this life stage. Moreover, binge drinking may have a negative impact on growing bones, due to its detrimental effects on bone mass and strength Individuals who are exposed to tobacco and nicotine during adolescence are at higher risk of substance abuse of other toxic substances. Vaping, which is an increasing public health issue, has also been associated with negative dental outcomes, and there is some suggestion that substances contained in vaping liquids may be carcinogenic. Preliminary evidence also suggests that vaping may be associated with mental health challenges in a similar manner to tobacco smoking. 

Increased Risk of Developing Acne

Individuals are at a higher risk of developing acne during adolescence due to hormonal changes and imbalance. Acne can have a negative impact on the self image and self esteem of young people, and exert detrimental effects on mental wellbeing overall. Although several dietary factors have been proposed as being involved in the development of acne, evidence is not currently strong enough to propose direct, causal relationships between certain foods and food groups and acne development. However, reducing sugary and processed foods and ensuring an overall healthy, balanced diet is important and may help to support hormonal balance and good skin health. 

Increased Risk of Iron Deficiency Anaemia in Menstruating Individuals

Once menstruation begins, the risk of iron deficiency anaemia increases due to monthly bleeding. These risks can be exacerbated in individuals who are not achieving adequate iron levels through their diet. Vegetarians and vegans are also at a higher risk. 

Menstruating individuals experiencing iron deficiency may also have higher risk of developing depression and anxiety, because deficiency of iron causes altered levels of serotonin and dopamine. Serotonin and dopamine are two neurotransmitters involved in mood regulation. Furthermore, iron deficiency results in alteration to balances of the neurotransmitters glutamate and GABA, which have an excitatory and calming effect on the nervous system, respectively. Iron status should be monitored and supported through nutrition and, if required, supplementation warranted. 

Key Nutrients

Omega 3

Adolescents with higher intake of omega 3, in the form of EPA, have been observed to have better memory scores. A study demonstrated adolescents with higher omega 3 levels had lower impulsivity and better attention scores, and these findings were also observed in another study which observed a correlation between omega 3 and impulse and behaviour control. Research has also indicated that omega 3 be a key nutrient for supporting adolescents struggling with alcohol addiction. In terms of mental health, some research has indicated that the omega 3:6 ratio may be a key area for future research for psychosis, as some preliminary evidence has suggested alterations in the omega 3 pathway may be associated with increased risk of psychosis. A further study indicated that the balance between omega 3 and omega 6 may be a key consideration for depression, anxiety and psychosis, due to inflammation. However, further research is required to explore this area further. 

B Vitamins

Research has indicated that levels of B vitamins may decrease from childhood into adolescence, and this may result in the increase of homocysteine, a marker which may increase the risk of mental health conditions, cardiovascular disease and dementia later in life.  A study found that higher dietary levels of folate and B6 are related to reduce incidence of depression in both adolescent boys and girls. Higher dietary intake of B2 has also been observed to be associated with lower incidence of depression, but only in teenage girls. A further study indicated that lower levels of B1, B2, B3, B5, B6, and folate may increase the risk of mental illnesses. 

Vitamin D

Vitamin D levels have been observed to be a key consideration for reducing risk of obesity and type II diabetes. Vitamin D deficiency has been suggested to be a key nutritional consideration  for adolescents with mental health conditions. Low Vitamin D status has been associated with behavioural issues during adolescence. 

Practical Strategies

The British Nutrition Foundation recommends several key strategies for supporting health and wellbeing during adolescence. These will be explored below with relation to current research on these areas. 

Ensure Three Healthy Meals are Consumed Daily and Choose Snacks Wisely

Adolescents should aim to base meals and snacks around a wide array of vegetables and fruit, wholegrains, nuts, seeds, legumes, dairy, lean meat and fish daily. Sugar and salt should be limited, along with consumption of processed foods and snacks.  Research has indicated that adolescents are at a greater risk of having unhealthy dietary and lifestyle habits during this life stage. Moreover, research has also demonstrated that individuals who consumed a higher level of vegetables and fruit during adolescence had lower risk of developing type II diabetes later in life, which is additionally a key risk factor for cardiovascular disease and Alzheimer’s disease, amongst other conditions. Moreover, in a secondary school analyses, a strong association between nutritional variables and well-
being scores was apparent. Higher combined fruit and vegetable consumption was also observed to be significantly associated with higher well-being.

Ensure Iron Status Maintained

Menstruating individuals should ensure they are consuming good quality sources of iron daily. Sources include meat, fish, cacao, apricots, beans and nuts. If individuals are experiencing symptoms of iron deficiency anaemia should consult their doctor to request testing.  

Support Bone Health 

To support bone health across the lifespan,  increase intake of  calcium, protein, B Vitamins, Vitamin C, D and K, magnesium, potassium, iron, zinc, copper, and manganese and avoid the excessive consumption of phosphorus and sodium. Omega 3 fats and fibre should also be increased, whilst reducing sugar and saturated fat consumption

Make Hydration a Priority

6-8 glasses of fluid are recommended daily, and it is preferable that this should come from water. Sugary juices and sodas should be limited, and ideally avoided completely.

Maintain an Active Lifestyle 

Research has shown that few adolescents achieve the recommendations for physical activity requirements. Research has suggested that regular physical activity may help to promote better academic performance, cognitive function, brain structure, and brain activity in adolescents. Physical activity has also been suggested as a potential means od reducing risk of mental illness, and of supporting mental health during adolescence. 

Increase Sleep Duration

The British Nutrition Foundation recommends a minimum of 8 hours sleep a night, and that adolescents seek to have screen-free bedrooms, and screen-free time before going to sleep, whilst adopting a relaxing pre bedtime routine.

The author gratefully acknowledges the assistance and contribution of Linda Albinsson, BSc Nutrition Science (CNELM) with the research and creation of this resource