Diet and mental health, does nutrition have a role in the prevention of depressi

[Guest guest]

Diet and mental health, does nutrition have a role in the prevention

of depression?

http://www.uku.fi/nutritionepidemiologists/mental.htm

 

Background

While depression is one of the most important health problems in

western countries, there are only few studies about the role of

nutrition in prevention of depression. Most of these studies have

been published on the relationship between folate and depression and

between omega-3 fatty acids and depression. Patients with major

depression have had lower serum or erythrocyte levels of folate in a

number of case-control studies. Also, low blood levels of folate

have been linked to a poor response to antidepressant treatment. In

some studies there has also been an inverse relationship between

blood folate levels and the severity of depression.

 

Folate, cobalamin and depression, possible mechanisms behind the

association

The association between the blood concentrations of these vitamins

and depression has been explained by their ability to decrease the

serum total homocysteine (tHcy) levels and by their connection with

monoamine metabolism in the central nervous system. Thus, a

deficiency of folate and cobalamin results in an increase in tHcy,

which in turn may aggravate depression. Bottiglieri et al (2000)

found that in psychiatric inpatients high concentrations of tHcy

were associated with more severe depression measured with the

Hamilton Depression Rating Scale. Recently, Bjelland and co-workers

found an increased risk of depression in the general population in

subjects with high plasma levels of tHcy. However, the results are

inconsistent.

 

Still unsolved questions:

Although there are reports of earlier cross-sectional and case-

control studies and clinical trials, no studies have been published

on the relationship between dietary folate and the incidence of

depression. In fact, it is not known whether the association between

low levels of folate and depression is caused by a low intake, poor

absorption or higher need of folate - or whether low blood levels of

folate are the result of a poor appetite as a symptom of depression.

 

Our results and research interests

These results are part of MD, psychiatrist Tommi Tolmunen's doctoral

work and have been done in co-operation with Department of

Psychiatry, University of Kuopio.

 

…Cross-sectional analyses

At the moment, we have studied the association between dietary

intake of folate, cobalamin, pyridoxine and riboflavin and serum

levels of folate and tHcy with depressive symptoms. These analyses

have made of both cross-sectional and prospective study designs of

KIHD Study. First we investigated the association between dietary

folate, cobalamin, pyridoxine and riboflavin and current depressive

symptoms in a cross-sectional analysis of 2682 male participants of

KIHD Study. Those who had a previous history of psychiatric disorder

were excluded (5.6% of the cohort). Depressive symptoms were

assessed with the 18-item Human Population Laboratory Depression

Scale. Those who scored 5 or more at baseline were considered to

have elevated depressive symptoms (9.3% of the cohort). The

participants were grouped into thirds according to their dietary

folate intake. Those in the lowest third of energy-adjusted folate

intake had a 67% higher risk of being depressed than those in the

highest folate intake third. This excess risk remained significant

after adjustment for smoking habits, alcohol consumption, appetite,

body mass index, marital status, education, adulthood socioeconomic

status and total fat consumption. There were no associations between

the intake of cobalamin, pyridoxine or riboflavin and depression.

 

…Prospective analyses

We studied the association between dietary folate and cobalamin and

the incidence of severe depression requiring hospitalization using

prospective study design. The participants were classified into 2

categories according to the median intake of dietary folate. Those

below the median of energy adjusted folate intake had increased risk

of becoming hospitalized due to depression during the follow-up

period compared with those in the higher folate intake group.

 

…About homocysteine and depression

We have also studied the association between serum folate and tHcy

with the current depressive symptoms using the KIHD Study 4-year re-

examination study population. These results are not published yet.

 

…What about the genes?

Present research interest in homocysteine-folate metabolism and the

risk of depression is to study interaction of folate and

homocysteine with genes and risk of depression. Genes available for

these analyses are cystathione -synthetase (CBS ile278thr), 5,10-

methylenetetrahydrofolate reductase (MTHFR ala223val) genes and

three mutations in PON1 genes and one in PON2 gene. Material

available for these analyses is KIHD Study 4-year visit cohort,

n=1038 men. Gene-nutrient interactions are a part of nutritionist

Anu Ruusunen's doctoral thesis.

 

Taken together:

Our results indicate that the nutrition may have a role in the

prevention of depression. We can not fully exclude the possibility

that the relation between depression and dietary folate could be

explained by other healthy features of a folate-rich diet. For

example, folate-rich vegetables and grains contain little saturated

fat. However, adjustment for intake of total fat, fiber and vitamin

C did not change the results significantly in our studies. It could

also be that poor eating habits, low physical activity, smoking and

excess alcohol consumption cluster in same people, who in any case

would be at risk of mental health problems - either because of their

lifestyle or despite it. However, adjustment for several possible

risk factors associated with lifestyle did not change the main

results in our studies.

 

More information:

tommi.tolmunen, aasaarel,

sari.voutilainen

 

Tommi Tolmunen, Sari Voutilainen, Jukka Hintikka, Tiina Rissanen,

Antti Tanskanen, Heimo Viinamäki, George A. Kaplan, Jukka T.

Salonen. Association of Dietary Folate and Depressive Symptoms are

associated in Middle-Aged Finnish Men. Journal of Nutrition

2003;133:3233-3236. PDF

 

Bottiglieri T, Laundy M, Crellin R, Toone BK, Carney MWP, Reynolds

EH. Homocysteine, folate, methylation, and monoamine metabolism in

depression. J Neurol Neurosurg Psychiatry 2000;69:228-232.

 

Bjelland I, Tell GS, Vollset SE, Refsum H, Ueland PM. Folate,

vitamin B12, homocysteine and the MTHFR 677C T polymorphism in

anxiety and depression. Arch Gen Psychiatry 2003;60:618-626.

 

Penninx BW, Guralnik JM, Ferucci L, Fried LP, Allen RH, Stabler SP.

Vitamin B12 deficiency and depression in physically disabled older

women: Epidemiologic evidence from the Women`s Health and Aging

Study. Am J Psychiatry 2000;157:715-721.

 

Alpert JE, Mischoulon D, Nierenberg MD, Fava M. Nutrition and

depression: focus on folate. Nutrition 2000;16:544-581.

 

Alpert JE, Fava M. Nutrition and depression: the role of folate.

Nutr Rew 1997;55:145-9.

 

Morris SM, Fava M, Jacques PF, Selhub J, Rosenberg IW. Depression

and folate status in the US population. Psychoter Psychosom

2003;72;80-87.

 

Coppen A, Bailey J. Enhancement of the antidepressant action of

fluoxetine by folic acid: a randomised, placebo controlled trial. J

Affective Disord 2000;60:121-130.

_________________

JoAnn Guest

mrsjoguest

www.geocities.com/mrsjoguest/Genes