INTRODUCTION:

Soft drinks are one of the most consumed non-alcoholic beverages throughout the world, and have substantial public health consequences. It has become a highly visible and controversial public health and public policy issue. The recent trend of increasing diet drink consumption is also of possible concern. The beverages may contain artificial sweeteners such as aspartame and saccharin; although there is controversy, potential adverse effects of these substances have been suspected. A number of studies examined links between soft drink consumption and various health outcomes. Malik VS et al (2010) & (malik VS 2006 p.274-288) and other studies implies that regular sweetened beverages contain large amounts of sugar and may have contributed to the obesity and diabetes epidemic in Western countries. One of these studies (Malik VS et al 2010) found that, people who consume sugary drinks regularly1 to 2 cans a day or more have 26% greater risk of developing Type 2 diabetes than people who rarely have such drinks. Moreover, a lot of other literatures ( Lindsay M. radio news 2003), (OCA 2005 )and many others associated soft drinks with lower intakes of milk, calcium, and other nutrients and with an increased risk of several medical problems such as diabetes, bone fracture, dental caries, heart attack, renal damage, mental problems and others. For instance a recent study found that, those who averaged one can of a sugary beverage per day had 20% higher risk of having a heart attack in men or dying from a heart attack than who rarely consumed sugary drinks. According to Organic Consumers Association (OCA) 2005, Soft drink consumption may be a major factor for osteoporosis and bone fracture as they are high in phosphates but contain virtually no calcium.

On the other hand, the acid in soft drinks so easily dissolves tooth enamel since the acidity of cola beverages is about the same as vinegar as OCA (2005) connotes. Most of all, there are several recent findings showing that, soft drink consumption is highly associated with depression and other mental problems. Among all the health hazards related with soft drink consumption, we are intended to investigate the association of soft drinks with depressive symptoms among university students in Ethiopia. Even if there is no data available in our setup related to level of consumption of soft drinks; we have observed the increased consumption of soft drinks especially among university students.

There were no studies available related to depression and its association with soft drinks in Ethiopia. But there were several studies showing the elevated prevalence of depression in Ethiopia. A study based on National Healthy Survey of Ethiopia (Hailemariam et al 2012) related to depression and associated factors showed that the prevalence of depressive episode was 9.1% (95% CI: 8.39-9.90) and in a Univariate analysis, residence, age, marital status, educational status, number of diagnosed chronic non communicable diseases (heart diseases, diabetic mellitus and arthritis) and alcohol drinking status were associated with depression. Another study (Tesera B. 2014 intr. Para.2) reported that depression contributes to about 6.5% of the burden of diseases and the pooled prevalence of the eight studies (Tesera B. 2014 Result .para.1) become 11% (95%), CI: (10.5-11.5) in Ethiopia. But these studies neglected the association of depression with soft drinks. Although, several studies in western countries evidenced the strong association between these attributes.

The exact mechanism of how soft drinks linked to depression is not well understood even if there are some experimental studies forwarded some biochemical findings. (Lindsay M. Ksl radio news 2013) presented a UCLA (2002) study which found that, consuming excessive amounts of sugar reduces the production of the brain chemical called BDNF. “Without BDNF, our brains can’t form new memories and we can’t learn (or remember) much of anything. Another study from the University of Copenhagen found that low BDNF levels were linked to depression and dementia (Lindsay M. March 28th, 2013 ksl radio news).There were a number of studies supporting this association. Among them, a recent study (Chens & Redei, 2013) looked at data from 263,925 for about 10 years and discovered that, people who drank more than four cans or cups of soda per day were 30 percent more likely to be depressed than those who did not drink sweetened drinks.

There were also several cross sectional studies (Yu B, et al2014) (Xuguang Guo, et al 2014) (Shi Z, et al 2010) and others which were showing the elevated prevalence of depression and other mental disorders among the population consuming soft drinks on usual bases. And we hope our study will also become one of these studies further revealing the link between these factors and contributes to provide concrete scientific knowledge to our community. Depression is the most common and disabling mental illness in the globe. It accounts for about 6.5% of the burden of diseases in Ethiopia (Tesera B. 2014 intr. para.1). Depression is found to be the fourth most important contributor to the global burden of disease and comprises in year 2000 4.4% of the total disability adjusted Life Years (WHO, 2001). According to the World Federation of Mental Health (WFMH) report of 2012, depression interferes with the daily life of people and causes pain for both patients and those who care about them.

Since depression has no one exact cause, rather associated with numerous risk factors which were all known yet; it is very crucial to search for and/ confirm its risk factors in order to tackle them. Among the risk factors the one recently founded was consumption of soft drink. In several cross-sectional studies, frequent drinking of sweetened beverages (mainly soft drinks) was associated with higher prevalence of depression, suicidal thoughts and acts, and other mental stress. A cross sectional study conducted in China (Yu B, et al 2014) among 3667adults shows that the prevalence of elevated depressive symptoms was 7.6% (SDS ≥50) among adults who consume soft drinks. Another study in Australia (Shi Z, et al 2010) reported that adults who consumed over a litre of soft drink per day had approximately 60% of higher prevalence of depression, suicidal ideation, or mental problems. Xuguang Guo, et al (2014) also found that higher consumption of soft or fruit drinks at baseline were monotonically associated with a higher risk of depression. However, this relationship could be bi-directional and cross-sectional analyses cannot rule out reverse casuality. There was only one prospective cohort study related to this area. A 10 years long cohort study on a very large sample found that, the prevalence of depression was slightly more than 4% and those who drank four cans of soft drinks a day were 30% more likely to have depression than those who drank none. For anymore, there were no accessible studies related to this issue in Ethiopia and other African countries. Yet the issue is controversial and need further studies. And the aim of this study is to further investigate this issue and, to fill the information gap in our country and in the world as whole regarding this health attributes. It is very crucial to help those who consume too much of soft drink to understood its counter effect on their health and, decides upon their level of consumption. It can also enable the government to be more awarded of the issue i.e. the prevalence of depression and its risk factors including soft drinks, and to take possible measures towards it. It can pave a way to reduce the debilitating effect of depression up on the productivity of students and of the country .It also improves the group member’s basic research knowledge and skill. Moreover, the hypothesis generated by this study can initiate others to conduct more inclusive and cohort studies which can confirm this hypothesis.

METHODOLOGY:

Institutionalized Descriptive cross sectional study was conducted to assess the prevalence, factors associated with soft drink consumption and the depressive symptoms, among Hawassa university students, Hawassa, Ethiopia, 2007E.C. The sample was selected by using proportionate simple random stratified sampling technique. 1130 students were selected from second and third year batches of all courses in the University. The sample was stratified (1130) into male and female strata based on their Gender. The male and female strata consists of 750 Males and 380 females respectively. By using simple random stratified sampling technique, equal number of respondents were selected from each stratum (150males and 150 females) proportionately. Data was collected by using a Structured self -administered questionnaire, containing demographic data, factors determining the soft drink consumption and assessment of depressive symptoms based on Hamilton depression scale.

ETHICAL CLEARANCE:

Ethical clearance was obtained from Institutional Review Board, Hawassa University. No materials were used during the study. Source of funding not applicable.

FINDINGS:

(A) Socio-demographic Data and Factors Affecting Soft Drink Consumption:

A total of 300 respondents were involved in the study with a response rate of 100%. It comprises of 150 males and 150 females which were selected via sex based proportionate stratification. Socio-demographic profiles of the respondents revealed that more than half (56.33%) of them were of second year batch. The majority were in the age between 20-24 years old (84.67%), Unmarried (89.33%), Orthodox (58%) and from urban (62.66%). The dominant ethnic groups were Amhara( 35% ), followed by Oromo(21.33%). Forty five percent of respondents have a monthly expenditure of greater than 500birr and 89% of them were sourced by their parents. The factors influencing the soft drink consumption results were depicted in Table-1.

(B) Depressive symptoms:

The most prevalent depressive symptoms were: Feeling loss of interest in activities(35%), Changes in their weight (31%), Having thoughts and feelings of incapacity, fatigue or weakness related to activities(30%); Worrying about minor matters(29.66%); Feeling impaired ability to concentrate(28.66%), Awakening during the night, except for purposes of voiding(23.67%); Feeling agitation(23.67%) and appetite loss(22%).Only 12.67% have experienced depressed mood after soft drink consumption. Out of total respondents, 21.67% thought that they drank too much, 21% were complained by their friends/family and 22% tried to stop soft drink consumption. The percentages were depicted in Table-2. The Percentage distribution of depressive symptoms associated with soft drink consumption were depicted in Table-3.

Table:1 The students studying second and third years in College of Medicine and Health Science in 2007 E. C.

S.No	Variable	Option	Male		Female		Total freq.	Total %
S.No	Variable	Option	Freq.	%	Freq.	%	Total freq.	Total %
1	Habit	Yes	120	80%	94	62.67%	214	71.33%
1	Habit	No	30	20%	56	37.33%	86	28.67%
2	How often	Every day	7	5.83%	26	27.66%	33	15.42%
		2-3/wk	46	38.33%	26	27.66%	72	33.64%
		4-6/wk	14	11.67%	11	11.7%	25	11.68%
		<1/wk	53	44.17%	31	32.98%	84	39.25%
3	For how long	<1yr	28	23.33%	19	20.21%	47	15.67%
		2-3yrs	24	20%	22	23.4%	46	15.33%
		>3yrs	68	56.67%	53	56.38%	121	40.33%
4	Type of drink	Sweetener	66	55%	48	5.1%	114	38%
		Energizer	32	26.67%	21	22.34%	53	17.67%
		Soda	16	13.33%	13	13.83%	29	9.67%
		Other	6	5%	2	2.12%	8	2.66%
5	With whom	Family members	27	22.5%	29	30.1%	56	18.67%
		Friends	88	73.33%	61	64.89%	149	49.67%
		Other	5	4.17%	4	4.25%	9	3%
6	When	During food	18	15%	18	19.15%	36	12%
		Before food	2	1.67%	3	3.2%	5	1.66%
		After food	46	38.33%	18	19.15%	64	21.33%
		When feeling sad	8	6.67%	3	3.2%	11	3.67%
		When feeling thirsty	7	5.83%	12	12.76%	19	6.33%
		During break time	18	15%	16	17.02%	34	11.33%
		No specific time	21	17.75%	24	25.53%	45	15%
	Which brand	Coca cola	43	35.83%	42	44.68%	85	28.33%
		Pepsi	18	15%	8	8.51%	26	8.67%
		Mirinda	41	34.17%	28	29.8%	69	23%
		Soda	8	6,67%	5	5.32%	13	4.33%
		Sprite	5	4.16%	7	7.44%	12	4%
		Fruit flavored	5	4.16%	2	2.13%	7	2.33%
		Other	0		2	2.13%	2	0.67%

Table 2 : Assessment items for depressive symptoms.

Sl. No	Depressive symptoms	Frequency	%
1	Depressed mood after soft drink consumption	38	12.67%
2	Feeling guilt	50	16.67%
3.	Difficulty in falling asleep	55	18.33%
4	Awaking during the night, except for purposes of voiding	71	23.67%
5.	Have thoughts and feelings of incapacity, fatigue or weakness, related to activities	90	30%
6.	Feel loss of interest in activities	105	35%
7	Feel impaired ability to concentrate	86	28.66%
8.	Feel agitation (playing with hair, hand biting of lips, etc.,)	71	23.67%
9.	Worrying about minor matters	89	29/66%
10.	Have appetite loss	66	22%
11.	Experienced changes in their weight (loss or gain)	93	31%
12.	Try to stop drinking them	66	22%
13.	Thought that they drank too much	65	21.67%
14.	Family or friends complained about the amount they drink	63	21%

Table:3 Percentage distribution of depressive symptoms associated with soft drink consumption, HU,CMHS, Ethiopia. (N=300)

S.N	Factors	Options	Number of Depressive symptoms
			No symptom		1-4 Ds		5-8 Ds		>8 Ds
			Freq.	%	Freq	%	Freq	%	Freq	%
1	Habit of SDC	Yes	50	23.4%	96	44.86%	58	27%	10	4.7%
1	Habit of SDC	No	46	49%	21	22.3%	17	18%	2	2.1%
2	How often	Every day	3	9%	19	57.6%	9	27.3%	2	6 %
		4-6/wk	7	25 %	11	39.3%	9	32.1%	1	3.6%
		2-3/wk	13	18.6 %	37	52.9%	17	24.3%	3	4 %
		<1/wk	25	30 %	32	38.5%	21	25 %	5	6 %
3	Duration of consumption	<1yrs	11	24.4%	15	33.3%	14	31%	5	11%
		2-3yrs	8	17.8%	20	44.4%	16	35.6%	1	2 %
		>3yrs	28	23.1%	62	51.2%	27	22.3%	4	3.3 %
4	Preferred time of consumption	During food	8	25%	10	31.3%	13	40.6%	1	3 %
		Before food	0	0	5	83.3%	1	16.7%	0	0
		After food	16	25%	28	43.7%	15	23.4%	5	7.8%
		When sad	2	22.2%	3	33.3%	4	44.4%		0
		When thirsty	6	28.6%	10	47.6%	3	14.3%	2	9.5%
		During break time	10	31%	17	53%	4	12.5%	1	3.2%
		No specific ation of time	8	18.2%	20	45.5%	16	36.4%	0	0
5.	Type of soft drink brand	Coca cola	20	24.1%	35	42.2%	27	32.5%	1	1.2%
		Pepsi	6	26.1%	10	43.5%	4	17.4%	3	13%
		Miranda	15	21.4%	37	52.9%	13	18.6 %	5	7.1%
		Tonic	2	13.3%	5	33.3%	7	46.7%	1	6.7%
		Sprite	1	10 %	6	60 %	3	30 %		0
		Fruit flavored drinks	5	71.4%	2	28.6%		0		0
		Other	4	80%		0	1	20 %		0

Table 4: Level of depression among the population who have habit of consuming soft drinks

S.No	Level of depression	Male		Female		% from total population
S.No	Level of depression	Freq	%	Freq	%	% from total population
1	Mild depression	56	46.67%	39	41.49%	44.39%
2	Moderate depression	26	21.67%	32	34.1%	27.1%
3	Severe depression	5	4.17%	6	6.38%	5.14%
4	No depression	33	27.5%	17	18.1%	23.36%

Table: 5 Chi -square association between depressive symptoms and factors related to soft drink consumption, Hawassa University.

S. N	Factors	Options	Number depressive symptoms				c²*cal.*	Df	p-value	c² tab. at α=0.05
S. N	Factors	Options	No symp toms	1-4 sym ptoms	5-8 sym ptoms	>8symptoms	c²*cal.*	Df	p-value	c² tab. at α=0.05
			No.	No.	No.	No.
1	Habit of SD consumption	Yes	`50	96	58	10	25.2	3	0.001	7.8
1	Habit of SD consumption	No	46	21	17	2
2	Frequency of consumption	Every day	3	19	9	2
		4-6/wk	7	11	9	1	18.5	9	0.02	16.9
		2-3/wk	13	37	17	3
		<1/wk	25	32	21	5
3	Duration of consumption	<1yrs	11	15	14	5
		2-3yrs	8	20	16	1	10.1	6	0.1	12.6
		>3yrs	28	62	27	4
4	Type of soft drink	Sweetener	30	58	27	3
		Energizers	12	27	15	2	9.23	9	0.2	16.9
		Tonic	4	15	11	1
		Other	4	1	5	0
5	Preferred group for consumption	Family	11	27	18	0	7.87	6	0.2	12.6
		Friend	35	69	36	9
		Other	3	2	4	0
6	Preferred time of consumption	During food	9	11	13	2
		Before food	0	6	1	0
		After food	17	28	15	5	31.5	18	0.02	28.87
		When sad	2	3	4	0
		When thirsty	6	10	3	3
		During break time	10	17	4	1
		No specific of time	8	20	16	0
	Preferred type soft drink brand	Coca cola	20	35	27	1	12.6	18	0.2	28.9
		Pepsi	6	10	4	3
		Miranda	15	37	13	5
		Soda	2	5	7	1
		Sprite	1	6	3	0
		Fruit flavored drinks	5	2	0	0
		0ther	4	0	1	0

Similar difference was implicated between number of depressive symptoms and preferred time of consumption (c²=31.5, p=0.05 & α=0.05). However, no significant association was detected between level of depression and duration of consumption, type of soft drink and group of people they prefer to consume together with respective p-value 0.1, 0.2 and 0.2 respectively at α=0.05.

DISCUSSION:

Very large portion (71%) of the study subjects had a habit of soft drink consumption. This finding was in concordance with that of AJPH (2013) and (Cynthia L. 2011); which shows that consumption of soft drink is highly increasing throughout the world, especially in low income countries. The possible reason may be this very thing i.e. income status of the students, availability of soft drinks and peer influences. Males consumed more beverages than did females, which is similar with NHNS (1999-2002). Depression is the most common and disabling mental illness in the globe. It accounts for about 6.5% of the burden of diseases in Ethiopia (Tesera B. 2014 intr. para.1). Depression is found to be the fourth most important contributor to the global burden of disease and comprises in year 2000 4.4% of the total disability adjusted Life Years (WHO, 2001). According to the World Federation of Mental Health (WFMH) report of 2012, depression interferes with the daily life of people and causes pain for both patients and those who care about them. This study shows that there was statically significant difference in number of depressive symptoms between student’s habits of soft drink consumption, showing elevated number of depressive symptoms among those who have habit of consumption. This finding is showing that there is a positive link between soft drinks and depression or depressive symptoms. However, there is so much difference between them in showing the strength of the link between those variables. This may be associated with the methodological difference in type of study design used, type of population, type of soft drinks and degree of adjustment for confounding factors.

The study findings revealed that, there was no observable increment in level of depression with increased frequency & duration of consumption which is somewhat contrary with other studies. This may reveal that consumption level of this population was not high enough to solely trigger the clinical depression, but it did with mild depression. That means the consumption among this population was almost at the same status and there was no much over consumers. This is why mild depression was overtly elevated among those who have habit of consumption. It may also show that there were other factors contributing to depression (especially to high level of depression) among university students than soft drink consumption.

The prevalence of depressive symptoms was approximately about 77% among those who habitually consume soft drinks, which was about 30% more than that of none or rare consumers. Nearly 77% of those who had habit of consumption had experienced at least one depressive symptom, which is only 46% among non consumers. More depressive symptoms were observed in those who consume everyday (91%). However, the observed frequency and duration of soft drink consumption in this population was less favorably with the level of depression. Slightly elevated trend of depression was seen among those who were taking before food, when sad and when thirsty. There was no significant difference observed between type of preferred soft drink brand and level of depression. But, there was relatively high tendency of depression in those who prefer Coca cola, Pepsi, tonic and Sprite than others. Fruit flavored drinks is less associated with depression. Mild depression was highly observed among those who have habit of consumption accounting for 45%, which is about two times more than those who have no habit. Similarly, severe depression was about two times higher among the consumers than non consumers. On the other hand, the majority (49%) of non consumers had no depression which was double of that among consumers. Among the study population, 46.67% mild level of depression was seen followed by 21.67% of moderate depression, 4.17% of severe depression and 33% of no depression in males respectively. In females, 41.39% of mild depression, 27.1% of moderate depression, 5.14% severe depression and followed by 23.36% of no depression was observed. Statistically significant association was also detected between the level of depression and the student’s preferred times of consumption. Relatively, elevated trend of depression was observed in those who took before food, when sad and when thirsty. This may be due to the fact that, those who took before food or when thirsty may have high tendency of depression for they took in empty stomach which could increase its absorption, thus increase its counter effect on the body. Those who took when sad may wrongly associate the existing depressive symptoms with soft drinks. Paradoxically, the others may took together with coffee or other stimulants which was found to decrease the risk of depression by Xuguang Guo et al., (2014)

CONCLUSION:

As general, moderate level of soft drink consumption were observed among students of HU, CMHS. Only 15% of the total sample was taking soft drinks on usual basis. This consumption level was significantly associated with some number of depressive symptoms which could be classified as mild or moderate depression. Those who take soft drinks once or more times a day would be more likely develop depressive symptoms, and they tend to develop more severe depression as amount increases. However, the consumption of two to six times per week is also likely to contribute some depressive symptoms. Any consumption level may aggravate the existing level of depression. Soft drink consumption was found to be in favor of depression irrespective of duration of consumption & type/brand of soft drinks. But it was significantly altered by preferred time of consumption. This study can be used by anybody to decide up on their consumption level of soft drinks and to take possible measures so as to decrease its counter effect on their health. Those who recurrently experiencing depressive symptoms may need to look unto the amount of soft drinks they are consuming as it could be one risk. However, one thing to be underlined is that this study cannot impose any limitations regarding their consumption status rather than giving suggestions.

ACKNOWLEDGEMENT:

We would like to acknowledge Hawassa University, College of Medicine and Health Sciences, School of Nursing and Midwifery, Department of Nursing for giving this opportunity for us which can equip us with the knowledge and skill of research and can help us a lot in our future careers. Finally, our acknowledgment would also extend to our study participants for their involvement and genuine answers.

REFERENCES:

1. Cynthia L. Ogden, M.R.P. Brian K. Margaret D. Carroll, M.S.P. H. and Shogun Park, / Consumption of Sugar Drinks in the United States/ 2005–2008, August 2011. NCHS Data Brief

2. Federal Ministry of Health (FMOH), author. National Mental Health Strategy of Ethiopia. Addis Ababa: 2012. (2012/13, 2015/16)

3. Hailemariam, Fasil Tessema, et al., The prevalence of depression and associated factors in Ethiopia: findings from the National Health Survey. Oct. 2012

4. Lindsay Maxfield, Diet soda, beverages linked to depression, KSL News radio March 28th, 2013/http//www.ksl.com/news

5. Malik VS, Popkin BM, Bray GA, Despres JP, Willett WC, Hu FB. Sugar-sweetened beverages and risk of metabolic syndrome and type 2 diabetes: a meta-analysis. Diabetes Care. 2010.

6. Malik VS, Schulze MB, Hu FB (2006) Intake of sugar-sweetened beverages and weight gain: a systematic review. The American Journal of Clinical Nutrition 84: 274–288.

7. Organic Consumers Association (OCA), Health Hazards of Drinking Coca-Cola and other Soft Drinks, February 16, 2005: http://www.newstarget.com/004416. html

8. Shi Z, Taylor AW, Wittert G et al., (2010) Soft drink consumption and mental health problems among adults in Australia

9. Tesera Bitew. Prevalence and Risk Factors of Depression in Ethiopia: A Review/ Ethiop J Health Sci. Apr 2014

10. WFMH, author. Depression: A Global Crisis World Mental Health Day. 2012

11. WHO, Author. Mental health Report: new understanding, new hope. 2001

12. Xuguang Guo, Yikyung Park, Neal D. Freedman, Rashmi Sinha, Albert R. Hollenbeck Aaron Blair, Honglei Sweetened Beverages, Coffee, and Tea and Depression Risk among Older US Adults. April 17, 2014

13. Yu B, Zhang Q, et al., Soft drink consumption is associated with depressive symptoms among adults in China, 2014. [pubmed].

Received on 31.07.2015 Modified on 24.08.2015

Int. J. Nur. Edu. and Research 3(4): Oct.-Dec., 2015; Page 393-399

DOI: 10.5958/2454-2660.2015.00029.0

Assessment of depressive symptoms related to overconsumption of soft drinks among university students, Hawassa University, Hawassa, Ethiopia

METHODOLOGY:

FINDINGS:

Table:1 The students studying second and third years in College of Medicine and Health Science in 2007 E. C.

REFERENCES: