FX Medicine

Home of integrative and complementary medicine

A Functional Approach to Children and Mood

Lisa_McDonald's picture
  • A Functional Approach to Children and Mood

While often very adaptable, children are just as vulnerable to mood imbalances as adults. Sometimes, these feelings can be more intense and dificult to manage. A holistic and functional approach can be helpful to understanding the underlying cause of any changes in mood and how you might address these.

What do mood changes look like in a child?

Children may have thoughts and feelings that are dificult to articulate, so it is helpful to look for signs of mood issues. Symptoms may include: sadness, guilt, loss of interest in activities, sleep disturbances, changes in appetite, decreased energy, dificulty concentrating, hypersensitivity to failure, irritability or aggression. Some of these symptoms may be intense and require review by a qualiied specialist.

There may be many underlying aspects why a child may experience anxiety, depression or changes to mood that should be explored.

Gut-brain axis

The gut-brain axis describes the complex bidirectional communication between the gut and the brain and includes the interaction of the microbiome of the gut in this process.[1-4] It is inluenced by the immune system and is often linked to mood concerns such as depression and anxiety.[1-4]

Children may complain of stomach aches associated with mood concerns and it is important to consider the impact of stress and mood on the gut. Probiotics and herbs such as chamomile, lemon balm, slippery elm, licorice, fennel, and St Mary’s thistle may be beneficial.

Sugar dysregulation and diet

Sugar dysregulation may be associated with anxiety and depression. Studies suggest that consuming a diet high in reined carbohydrates is associated with mood changes including depression.[6,7] A diet high in red meat, takeaway, reined foods and sugary foods are associated with depressive symptoms while a diet rich in fruit, vegetables, ish and wholegrains is protective against these symptoms.[5,6,8]

Poor sleep

Sleep problems amongst children is simultaneously part of the criteria for, and a contributing factor to, mood disturbances. Insuficient or poor quality sleep is also linked to gastrointestinal disturbances,[12] poor blood glucose regulation[9,10] and varying nutrient levels (e.g. low levels of vitamin B12 or magnesium).[11,13] Other important considerations may be reviewing levels of histamine and glutamine in the diet, levels of stress and bedtime routine. Lemon balm, passionlower and chamomile may be beneicial to assist with sleep.

Food intolerances, immune system and inlammation

Food intolerances may increase histamine levels.[16] Abnormal histamine levels have been associated with brain inlammation and mood disorders.[14,15] Studies suggest there is also an association between allergies, low-grade inlammation and depression.[14,15,17-19] Supporting effective histamine metabolism may be beneicial to balancing histamine levels.

Pathogens and infections

Pathogens may affect mood. Research suggests an association between streptococcal infections and neuropsychiatric disorders such as acute obsessive-compulsive disorder;[21] an anxiety-mood disorder in children. This is called paediatric autoimmune neuropsychiatric disorders associated with streptococcal infections or PANDAS.20 Other infections may also impact mood and may therefore be necessary to review possible infections.[22] Consider antimicrobial and antiparasitic herbs that are suitable for children such as calendula, cinnamon, echinacea, elderberry, garlic and thyme.



Methylation is an important biochemical process in the body, part of which produces S-adenosylmethionine (SAMe); an important methyltransferase which is utilised for neurotransmitter synthesis.[26] Low folate and vitamin B12 – important cofactors in the methylation cycle – are also associated with low mood.[23,24] As a result of these factors, poor or imbalanced methylation may affect mood.

Insufficient or suboptimal vitamins and minerals

Consider the levels of these nutrients and their possible contribution to low-mood in children.



Vitamin B12

Reduced intake of vitamin B12 is associated with mental health concerns in adolescence. Low serum folate and vitamin B12 is associated with depression.[23,24]


Low plasma zinc has been linked with anxiety and zinc supplementation may assist depression.[27-29] 

Vitamin B6/pyridoxal-5-phosphate (P5P)

Important for neurotransmitter synthesis and tryptophan metabolism.  low vitamin B6 is associated with depression and anxiety.[30]


Studies suggest a high intake of magnesium is associated with reduced mental health concerns in adolescence.[25]

Omega-3 fatty acids

A diet low in omega-3 fatty acids has been associated with depression and children may benefit from increasing foods rich in these.[31,32]

Vitamin D

Low vitamin D may be associated with depression.[33,34] 

Environmental toxins 

Consider the impact of accumulation of environmental factors when reviewing children and mood. Lead and mercury levels are particularly associated with depression, anger and anxiety.[35]

Gene variants

Increasing research demonstrates associations between gene variants, or single nucleotide polymorphisms (SNPs), and mental health concerns. Reviewing SNPs associated with biochemical pathways or systems may aid the prioritisation and initiation of further pathology testing where required.

The genes that may be useful to review in children with mood concerns include: 

GUT-brain axis





Fucosyltransferase 2

Associated with bacterial attachment to intestinal mucosa; gastrointestinal diversity and vitamin B12 absorption.


Human Leukocyte Antigen

Associated with gluten intolerance. There may be an association between gluten intolerance and mood such as anxiety and depression.36,37

Fatty acids and brain function





Brain-derived neurotrophic factor

Involved in neuroplasticity. Lower BDNF activity is associated with increased risk of mood dysfunction and depression.


Fatty acid desaturase 1

Involved in omega-6 and omega-3 fatty acid metabolism.

Neurotransmitter synthesis





Monoamine oxidase A

Involved in the metabolism of neurotransmitters dopamine, serotonin and noradrenalin. It is associated with aggression and anxiety.


Catechol-o-methyl transferase

Involved in metabolism of catecholamine such as dopamine, adrenalin, noradrenaline. May be associated with altered levels of these neurotransmitters and influence anxiety and depression.


Glutamic acid decarboxylase 1

Involved in the conversion of glutamate an excitatory neurotransmitter to gamma-aminobutyric acid, an inhibitory neurotransmitter. May be associated with mood related disorders.


Serotonin N-acetyltransferase

Involved in the synthesis of melatonin and may be associated with delayed sleep onset. 


Diamine oxidase

Involved in the degradation of histamine.






Methylenetetrahydrofolate reductase

Converts folate to methylfolate. Provides the methyl group needed to convert homocysteine to methionine.  Methionine is required for the production of SAMe, important for neurotransmitter production and synthesis.






Glutathione S-transferase P1

Involved in phase II detoxification and may play a role in the detoxification of harmful substances including modifying methylmercury metabolism.38






Fucosyltransferase 2

Associated with bacterial attachment to intestinal mucosa; gastrointestinal diversity and vitamin B12 absorption.


Transcobalamin 2

Associated with binding to vitamin B12 and transporting into cells.


Phosphatidylethanolamine N-methyltransferase 

Involved in enzyme that catalyses phosphatidylethanolamine to phosphatidylcholine.  Low choline is associated with anxiety.


Vitamin D receptor

Binds to an active form of vitamin D and facilitates its function. 

Mood concerns in children have a number of possible aetiologies and as part of a naturopathic and functional medicine approach, all of these aspects should be explored for optimal health outcomes for children.


  1. Petra A, Panagiotidou S, Hatziagelaki E, et al.  Gut-microbiota-brain axis and effect on neuropsychiatric disorders with suspected immune dysregulation. Clin Ther. 2015 May 1;37(5): 984-995. [Full Text]
  2. Carabotti M, Scirocco A, Maselli MA, et al. The Gut-brain axis: interactions between enteric microbiota, central and enteric nervous systems.  Ann Gastroenterol. 2015 Apr-Jun; 28(2):203-209. [Full Text]
  3. O'Mahony SM, Clarke G, Borre YE, et al. Serotonin, tryptophan metabolism and the brain-gut-microbiome axis.  Behav Brain Res. 2015 Jan15;277:32-48. [Abstract]
  4. Desbonnet L, Clarke G, Traplin A, et al. Gut microbiota depletion from early adolescence in mice: implications for brain and behaviour.  Brain Behav Immun. 2015 Aug;48: 165-73. [Abstract]
  5. Opie RS, O'Neil A, Itsiopoulos C, et al. The impact of whole-of-diet interventions on depression and anxiety: a systematic review of randomised controlled trials.Public Health Nutr. 2015 Aug;18(11):2074-2093. [Abtract]
  6. Gangwisch JE, Hale L, Garcia L, et al.  High glycemic index diet as a risk factor for depression: analyses from the Woman’s Health Initiative.  Am J Clin Nutr 2015 Aug;102(2):454-63. [Full Text]
  7. Knuppel A, Shipley MJ, Llewellyn CH, et al.  Sugar intake from sweet food and beverages, common mental disorder and depression: prospective findings from the Whitehall II study. Sci Rep 2017 Jul 27;7(1):6287 [Full Text]
  8. Oddy WH, Allen Kl, Trapp GSA, et al.  Dietary patterns, body mass index and inflammation: pathways to depression and mental health problems in adolescents. Brain Behav Immun 2018 Mar;69:428-439 [Abstract]
  9. Chojnacki, KC, Kanagasabai T, Riddell MC, Ardern CI. Associations between Sleep Habits and Dysglycemia in US Adults: A cross-sectional analysis.  Can J Diabetes. 2018 Apr;42(2):150-157. [Abstract]
  10. Jaser SS, Ellis D. Sleep iin adolescents and young adults with Type 1 diabetes: associations with diabetes management and glycemic control. Health Psychol Behav Med 2016 Jan1;4(1):49-55. [Full Text]
  11. Lichstein KL, Payne KL, Soeffing JP, et al. Vitamins and sleep: An exploratory study. Sleep med. 2008 Jan;9(1): 27-32. [Full Text]
  12. Fass R, Fullerton S, Tung S, Eet al. Sleep disturbances in clinic patients with functional bowel disorders. Americal Journal of Gastroenterology. May 2000; 95:1195-1200. [Abstract]
  13. Abbasi B, Kimiagar M, Sadeghniiat K, et al. The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial. J Res Med Sci 2012 Dec;17(12):1161-9 [Full Text]
  14. Goodwin, RD, Castro M, Kovacs, M. Major Depression and Allergy: Does Neuroticism Explain the Relationship?.  Psychosomatic Medicine: Jan-Feb 2006. Vol 68 Issue 1 p94-98. [Abstract]
  15. Theoharis TC, Stewart JM, Hatziagelaki E, et al. Brain fog, inflammation and obesity: key aspects of neuropsychiatric disorders improved by luteolin. Front Neurosci 2015; 9:255. [Full Text]
  16. Maintz L, Novak N. Histamine and histamine intolerance. The Americal Journal of Clinc. Nutrition. Vol 85, Issue 5. May 2007 p1185-1196. [Full Text]
  17. Nuutinen S, Panula P. Histamine in Neurotransmission and Brain Diseases. Adv Exp Med Biol. 2010;709:95-107. [Abstract]
  18. Leonard BE.  Inflammation and depression: a causal or coincidental link to the pathophysiology?  Acta Neuropsychiatr.  2018 Feb;30(1): 1-16. [Abstract]
  19. Miller AH, Raison CL. The role of inflammation in depression: from evolutionary imperative to modern treatment target.  Nat Rev Immunol. 2016 Jan; 16(1): 22-34. [Full Text]
  20. Zibordi F, Giovanna Z, Miryam C, et al. CANS: Childhood acute neuropsychiatric syndromes. Eur J Paediatr Neurol. 2018 Mar;22(2):316-320. [Abstract]
  21. Jaspers-Fayer F, Han SHJ, Chan E, et al. Prevalence of Acute-Onset Subtypes in Pediatric Obsessive-Compulsive Disorder.  J Child Adolesc Psychopharmacol. 2017 May;17(4): 332-341. [Abstract]
  22. Cadie M, Nye FJ, Storey P.  Anxiety and depression after infectious mononucleosis. Br J Psychiatry. 1976 Jun;128:559-61. [Abstract]
  23. Herbison CE, Hickling S, Allen KL, et al. Low intake of B-vitamins is associated with poor adolescent mental health and behaviour. Prev Med 2012 Dec;55(6):634-8. [Abstract]
  24. Coppen A, Bolander-Gouaille C. Treatment of depression: time to consider folic acid and vitamin B12. J Psychopharmacol. 2005 Jan;19 (1): 59-65. [Abstract]
  25. Black LJ, Allen KL, Jacoby P, et al. Low dietary intake of magnesium is associated with increased externalising behaviours in adolescents. Public Health Nutr. 2015 Jul;18(10):1824-30. [Abstract]
  26. Gao J, Cahill CM, Huang X, et al. S-Adenosyl Methionine and Transmethylation Pathways in Neuropsychiatric Diseases throughout life. Neurotherapeutics. 2018 Jan;15(1):156-175. [Abstract]
  27. Petrilli MA, Kranz TM, Kleinhaus K, et al. The Emerging Role for Zinc in Depression and Psychosis. Front Pharmacol. 2017; 8:414. [Full Text]
  28. Doboszewska U, Wlaz P, Nowak G, et al. Zinc in the monoaminergic theory of depression: Its relationship to Neural plasticity. Neural Plast. 2017;2017:3682752. [Full Text
  29. Russo AJ. Decreased zinc and increased copper in individuals with anxiety. Nutr Metab Insights. 2011;4:1-5. [Full Text]
  30. Hvas AM, Juul S, Bech P, et al. Vitamin B6 level is associated with symptoms of depression. Psychother Psychosom. 2004 Nov-Dec;73(6):340-3. [Abstract]
  31. Grosso G, Galvano F, Marventano S, et al. Omega-3 Fatty Acids and Depression: Scientific Evidence and Biological Mechanisms. Oxid Med Cell Longev. 2014 Mar 18. [Full Text]
  32. Liu JJ, Galfalvy HC, Cooper TB, et al. Omega-3 polyunsaturated fatty acid status in Major Depression with comorbid anxiety disorders. J Clin Psychiatry 2013 Jul;74(7): 732-738. [Full Text]
  33. Penckofer S, Kouba J, Byrn M, et al. Vitamin D and Depression: Where is all the sunshine?.Issues Ment Health Nurs. 2010 Jun;31(6):385-393. [Full Text]
  34. Anglin RE, Samaan Z, Walter SD, et al. Vitamin D deficiency and depression in adults: systematic review and meta- analysis. The British Journal of Psychiatry Feb 2013, 202(2) 100-107. [Abstract]
  35. Siblerud RL, Motl J, Kienholz E. Psychonmetric evidence that mercury from silver dental fillings may be an etiological factor in depression, excessive anger and anxiety. Psychol Rep. 1994. Feb; 74 (1): 67-80. [Abstract]
  36. Cecilio LA, Bonatto MW.  The prevalence of HLA DQ & DQ8 in patients with coeliac disease, in family and in general population. Arq Bras Cir Dig. 2015 Jul-Sep;28(3):183-185. [Full Text]
  37. Jackson JR, Eaton WW, Cascella NG, et al. Neurologic and Psychiatric Manifestations of Coeliac disease and gluten sensitivity. Psychiatr Q. 2012 Mar;83 (1): 91-102. [Full Text]
  38. Barcelos GR, Grotto D, de Marco KC, et al. Polymorphism in glutathione-related genes modify mercury concentrations and antioxidant status in subjects environmentally exposed to methylmercury. Sci Total Environ 2013 Oct 1;463-464:319-25. [Abstract]


The information provided on FX Medicine is for educational and informational purposes only. The information provided on this site is not, nor is it intended to be, a substitute for professional advice or care. Please seek the advice of a qualified health care professional in the event something you have read here raises questions or concerns regarding your health.

Share / Print: 
Lisa_McDonald's picture
Lisa McDonald

Lisa is a qualified clinical Naturopath with a special interest in nutrigenomics, methylation, MTHFR, chronic fatigue, mental health, gut health and biotoxin/mould illness (Chronic Inflammatory Response Syndrome - CIRS).

Following her Naturopathic qualification, Lisa completed further study with Seeking Health Institute, MTHFR Support Australia, GAPS and Fitgenes. Lisa also holds a Psychology degree and a Masters of Management. Presently, Lisa is completing Dr Richie Shoemaker’s Physician Certification program in Chronic Inflammatory Response Syndrome (CIRS) (mold/biotoxin illness) as well as qualifications in Nutritional and Environmental Medicine with ACNEM.

Currently, Lisa holds a position on the board of ARONAH (Australian Register of Naturopaths and Herbalists) whilst also running her clinical practice in Sydney. You can find Lisa at www.indigosagehealth.com.au