Loading...
 
Translate Register Log In Login with facebookLogin and Register

More colas (fructose, caffeine, phosphoric acid), lower vitamin D – July 2014

Association between Intake of Sugar-Sweetened Beverages and Circulating 25-Hydroxyvitamin D Concentration among Premenopausal Women.
Nutrients. 2014 Jul 28;6(8):2987-2999.
Duchaine CS1, Diorio C2 caroline.diorio at uresp.ulaval.ca
1 Cancer Research Center, Department of Social and Preventive Medicine, Laval University, Quebec City, Quebec G1V 0A6, Canada
2 Oncology Unit, Chu de Québec Research Center, Saint-Sacrement Hospital, Quebec, QC G1S 4L8, Canada
3 Deschênes-Fabia Center for Breast Diseases, Saint-Sacrement Hospital, Quebec, QC G1S 4L8, Canada


Summary by VitaminDWiki

Study did not take a position: fructose, caffeine, phosphoric acid - but did not mention Calcium

Vitamin D colas
26.9 ng <1/week
25.5 ng 1-3/week
23.4 ng >3/week

PDF is attached at the bottom of this page

See also VitaminDWiki

Abstract

Intake of sugar-sweetened beverages has increased in North America and seems to have several adverse health effects possibly through decreased circulating 25-hydroxyvitamin D OH)D) concentrations. The aim of this cross-sectional study was to evaluate the association between sugar-sweetened beverages intake and 25(OH)D concentrations among premenopausal women. Intake of sugar-sweetened beverages including colas, other carbonated beverages and sweet fruit drinks was assessed using a validated food frequency questionnaire among 741 premenopausal women. Plasma concentrations of 25(OH)D were quantified by radioimmunoassay. The association between sugar-sweetened beverages intake and 25(OH)D concentrations was evaluated using multivariate generalized linear models and Spearman correlations. A higher intake of colas was associated with lower mean 25(OH)D levels (67.0, 63.7, 64.7 and 58.5 nmol/L for never, <1, 1-3 and >3 servings/week, respectively; r = -0.11 (p = 0.004. A correlation was observed between intake of other carbonated beverages and 25(OH)D concentrations but was not statistically significant (r = -0.06 (p = 0.10)). No association was observed between intake of sweet fruit drinks and 25(OH)D concentrations. This study suggests that high intake of colas may decrease 25(OH)D levels in premenopausal women. Considering the high consumption of these drinks in the general population and the possible consequences of vitamin D deficiency on health, this finding needs further investigation.

PMID: 25072269

4 Discussion (extracted from attached PDF)

In this study, we found that higher intake of colas was associated with lower plasma concentrations of 25(OH)D among premenopausal women. Compared to non-consumers, women who drank more than three servings per week of colas presented a mean concentration of 25(OH)D that was 12.7% lower. In the latter category of colas consumption, 47.8% of women presented 25(OH)D concentrations below the recommended 50 nmol/L. Furthermore, 10.9% of these women had 25(OH)D concentrations below 30 nmol/L, which are considered as deficient concentrations. In comparison, only 16.3% of the women who never drank colas presented concentrations of 25(OH)D below 50 nmol/L of which only 0.3% (n = 1) were below 30 nmol/L.
Few studies have evaluated the association between intake of sugar-sweetened beverages and concentrations of 25(OH)D [24,25]. Following a two month diet, Garcia-Contreras and colleagues observed lower plasma 25(OH)D concentrations among rats consuming colas beverages compared to those who drank water [24]. In a cross-sectional study conducted among 411 obese children, Olson and colleagues found that both intake of sodas and juices were inversely associated with serum concentrations of 25(OH)D [25]. Our observations appear consistent with these studies conducted in population other than premenopausal women. One study, among women, has evaluated short-term effects of carbonated beverages consumption on serum concentrations of 1,25-dihydroxyvitamin D (1,25(OH)2D), the active form of vitamin D metabolized by the kidney and target tissues (such as breast, prostate, intestine, skin and bones) from 25(OH)D [38]. Concentrations of 1,25(OH)2D were lower in the group following a diet high in colas intake (1.4 L/day) compared to women following a diet without cola (85.4 nmol/L and 99.8 nmol/L, respectively), but the association was not significant. However, the study population was very small (eight women) and the serum concentrations of 1,25(OH)2D may not be the best biomarker to represent vitamin D concentrations [22]. Some authors have brought the idea that the effect of intake of colas on 25(OH)D concentrations was due to a replacement of the milk consumption by colas [25]. However, further adjustment for milk intake did not materially alter our results, suggesting that this factor does not confound the observed associations with 25(OH)D concentrations.
In our study, we found an inverse association of intake of colas with 25(OH)D concentrations and also a non-significant negative correlation between intake of other carbonated beverages and 25(OH)D concentrations. However, the intake of sweet fruit drinks was not associated with 25(OH)D concentrations. In comparison to sweet fruit drinks, carbonated beverages contain a higher concentration of fructose which is derived from corn syrup and used as a sweetener [39]. It has been suggested that fructose may have an effect on vitamin D metabolism [26]. In fact, the liver and kidneys, the principal sites of vitamin D metabolism, seem adversely affected by chronic fructose intake [40,41]. Moreover, one study conducted among rats with compromised renal function has shown that those fed with fructose had a reduction of 30%-40% in their 25(OH)D serum concentrations compared to rats fed with glucose [26]. This observation could explain the observed lower 25(OH)D concentrations with higher intake of carbonated beverages in our population. Furthermore, we observed no association between intake of diet colas and 25(OH)D concentrations (data not shown). However, the statistically significant association found with intake of colas was stronger than that of intake of other sweet carbonated beverages and thus may not be solely due to fructose.
A difference between colas and other sugar-sweetened beverages is that they contain caffeine which has been shown to increase the risk of osteoporosis [42,43]. To take this into consideration, we have made separate analyses of intakes of regular colas and caffeine free colas with 25(OH)D concentrations, and found similar negative correlations for both types of colas (r = -0.094, p = 0.012 for regular colas and r = -0.103, p = 0.006 for caffeine free colas). Thus, in the present study, caffeine does not seem to explain the results.
In contrast to other sugar-sweetened beverages, colas also contain phosphoric acid [5] and excessive exogenous phosphate intake is believed to cause vitamin D and calcium metabolism disorders [27,28]. One study has shown that intake of soft drinks containing phosphoric acid induced hyperphosphaturia and significant reductions in plasma concentrations of 1,25(OH)2D and 25(OH)D in immature rats [44]. All of these hypotheses need to be confirmed with additional studies, especially among humans.
This study has several strengths. The study sample was relatively large and the women were recruited in a short period of time. The measurement of plasma 25(OH)D concentrations was done with respect to high quality standards and the food frequency questionnaire used to assess intake of sugar-sweetened beverages was validated in other studies for its accuracy [33,34]. Several possible confounding factors (including vitamin D intake from food and supplements and milk consumption) of the association between intake of sugar-sweetened beverages and 25(OH)D concentrations were taken into account. Furthermore, the women of this study lived in the same geographic area, thus were exposed to the same climatic conditions and the assessments of leisure-time physical activity with the season at blood sampling allowed for a good adjustment for sun exposure. Thereby, the difference seen in 25(OH)D concentrations was probably not caused by differences in vitamin D intake, milk intake or sun exposure.
This study has also some limitations. Misclassification in the frequency of consumption of sugar-sweetened beverages is possible with the use of a food frequency questionnaire. Intake of sugar-sweetened beverages over the previous year was an estimation given by each participant. However, differential bias is unlikely because answers inaccuracies can hardly be related to 25(OH)D concentrations and if there was misclassification, it could only lead to an underestimation of the effect. Also, it was difficult to state on the biological mechanism because the nutrients contained in colas that can be responsible for the lower 25(OH)D concentration (fructose, caffeine and phosphoric acid) were already present in several other foods. Despite introduction of season at blood sampling and leisure-time physical activity in the models, the adjustment for sun exposure was not perfect because the information about clothing style, sunscreen use and time spent outdoors other than leisure-time physical activity were not available. It is therefore possible that colas drinkers spent less time outdoors than non-drinkers and this could lead to residual confounding. Intake of colas may also be viewed as a proxy of an unhealthy lifestyle which could include higher BMI, waist-to-hip ratio, intake of alcohol and calorie and smoking habit, and lower intake of calcium and vitamin D and levels of physical activity. However, in our data, the correlations between such 25(OH)D determinants and 25(OH)D concentrations that were statistically significant remained so even after the introduction of total intake of colas in the model. Furthermore, this study population was limited to premenopausal women so inference to other populations is difficult to make. Finally, the cross-sectional design of this study does not allow causal interpretation.

5. Conclusions

In conclusion, we found that premenopausal women with higher intake of colas had lower circulating concentrations of 25(OH)D. To our knowledge, this is the first report of this association in such type of population. Considering the importance of vitamin D concentrations in the maintenance of a good health and the possible links of vitamin D deficiency to some diseases, our findings need further investigation. In our study population, the intake of colas was not very high, but in other populations this consumption can be more significant and may affect 25(OH)D concentrations in a greater manner. Considering the high consumption of this type of beverage in the general population, further studies are needed to elucidate the findings of the present study.

Attached files

ID Name Comment Uploaded Size Downloads
4202 Cola.pdf PDF 2014 admin 30 Jul, 2014 13:05 188.23 Kb 315
See any problem with this page? Report it (FINALLY WORKS)