Soft drink consumption and preterm delivery risk in pregnant women

Sugar Substitutes

SWEET BUT DEADLY?

Health Concerns and Risks of Using Sugar Substitutes

Sweets and sugar-sweetened pop or soft drinks have recently been blamed for an increasing number of negative health conditions, such as overweight and diabetes. This has led solid soft drink consumers to turn to artificially sweetened soft drinks as substitutes. The safety of artificial sweeteners or sugar substitutes has been questioned but the impact of high intakes of artificial sweeteners on pregnant women has hardly been addressed.

The association between intakes of sugar-sweetened and artificially sweetened soft drinks and preterm delivery will be investigated.

Prospective cohort analyses of 20,000 women from the Buenos Aires national birth cohort (2012-2014) will be conducted. Their soft drink intake for more than 10 years will be assessed in mid-pregnancy through the use of a food-frequency questionnaire. The primary outcome measure will be preterm delivery at less than 37 weeks. Other information will be assessed through telephone interviews.

Conceptual Framework - The study will stress the importance of gaining knowledge about what foods are right to eat, especially during pregnancy and right after delivery, for both mothers and their offspring.

Expected Results -- will suggest a possible connection of the excessive intake of both artificially sweetened and non-carbonated drinks to an increased risk of preterm delivery. But additional research to bolster the expected results will be recommended.

Introduction

Background and Significance - Most everyone has a sweet tooth and most everyone loves to drink refreshingly cool soft drinks when it is humid or to quench thirst. When the obesity epidemic hit the news, sweets lovers easily welcomed the offer of artificial sweeteners as replacement of ordinary sugar. More so when the FDA issued a list of approved artificial sweeteners, which not only replace the dreaded sugar but also offer to solve weight problems. But the continued consumption of sweet soft drinks presents a particular problem concerning pregnant women and preterm delivery.

The Problem and Its Importance -- Preterm delivery is a major pregnancy complication and major cause of perinatal deaths and diseases. Current research states that both artificially sweetened soft drinks and sugar-sweetened soft drinks link to hypertension, a known risk for preterm delivery. Some evidence also suggests that these shorten gestation due to high blood glucose concentrations and low-dose methanol exposure.

Research Question -- How the regular intake of artificially sweetened soft drinks for more than 10 years will affect the preterm delivery of the respondents

Hypothesis - Both sugar-sweetened and artificially sweetened soft drinks may be related to an increased risk of preterm delivery.

Research Objective -- The study will explore the association between maternal soft drink consumption in pregnancy and preterm delivery

Literature Review

Food Additives

Food additives are defined as substances made part of a food product during processing or production of that food (Zieve, 2012). They are either direct or indirect. Direct additives are placed during processing to make that food more appealing. They are either man-made or natural. Indirect additives are either already found in food during or after processing. Strongest concern goes to man-made ingredients added to foods, especially artificial sweeteners or sugar substitutes, such as aspartame, saccharine and sodium cyclamate (Zieve).

The U.S. Food and Drug Administration or FDA publishes a list of tested food additives it finds safe (Zieve, 2012). These substances are described as "generally recognized as safe" or GRAS. At present, there are approximately 700 items of this kind in the list. Congress endorses these substances safe and of "reasonable certainty" that ingesting them will result in no harm. The list is regularly re-tested and sugar is one of them. Some of these, which are found harmful to people or animals, may be allowed if the level of harm is 1 out of 100. People with allergies or food intolerances are advised to check the labels for their protection. These reactions may be mild or severe (Zieve).

The FDA and the Department of Agriculture are the supervising and regulating agencies of food additives sold in the country (Zieve, 2012). But they caution those with allergies or intolerances and under special diets to exercise caution in choosing and buying their food products. For their production, the U.S. government requires all manufacturers to list and label all the ingredients on their products (Zieve).

Artificial Sweeteners and FDA

These are added to food and drinks are options to natural sugar in satisfying the craving for something sweet (ADA, 2012). They are also called low-calorie sweeteners, sugar substitutes or non-nutritive sweeteners. They are used in place of sugar and for fewer calories and carbohydrates. They are at least 100 times sweeter than ordinary or natural sugar, so one needs to use only a small amount. All sweeteners except aspartame are not metabolized by the body. This means that they cross body systems without getting digested. Thus, they do not provide calories (ADA).

The current list of FDA-approved artificial sweeteners reflects acesulfame K, aspartame, saccharin, sucralose and neotame (ADA, 2012). Food companies use them to make diet drinks, baked goods, frozen desserts, candy, light yogurt and chewing gum. They are also used as sugar substitute on the table. Stevia or Reb -- A is a product derived from the stevia plant, which is many hundred times sweeter than ordinary sugar. The USFDA recognizes it as generally safe for use as a food additive and sugar substitute in appropriate amounts. These substances contain no carbohydrates and, thus, do not raise blood glucose levels (ADA).

FDA Position on Aspartame Study

The USFDA (2007) reviewed the long-term carcinogenicity study of this artificial sweetener conducted by the European Ramazzini Foundation in Bologna, Italy. The USFDA did not find grounds to support the Foundation's conclusion that aspartame is cancer-causing. The USFDA thus retained its position on the safety of aspartame for use as artificial sweetener (USFDA).

The USFDA (2007) included aspartame among its list of approved artificial sweeteners in 1981. The body metabolizes this substance into amino acids aspartic acid, phenylalanine and methanol, which are produced also in the metabolism of other common foods. FDA requested the ERF for the data of the study but received only some of these data on February 28, 2006. It sought for the rest and for the review of the pathology slides of the study in June that year. Nut ERF did not send them as it did not agree to FDA's reviewing the slides. FDA had to make a position by using available data. It found significant shortcomings in the design, procedure, reporting and interpretation, which rendered its conclusion unreliable. Moreover, the data provided did not support the pathological findings of infection in test animals. FDA finds these changes incidental and spontaneous. None of the histo-pathological changes related to the use of aspartame. FDA suggested the conduct of another examination by an internationally-sponsored pathology working group on the tissue slides of the study to provide additional insight (USFDA).

Results from multiple studies on the safety of aspartame use include five, which reported negative chronic carcinogenicity (USFDA, 2007). One of them was a large epidemiology study, which found negative association between aspartame use and the occurrence of tumors. Based on these findings, it finds no reason to reverse its previous conclusion and position on the general safety of aspartame as a general-purpose food sweetener (USFDA).

Gender and Artificial Sweeteners

Women may appear to be the larger users of these substances, especially when they first broke into the market in the 50s and the 60s (Pena, 2012). But with the introduction of NutraSweet and the spread of great-tasting low-calorie products, these were as heavily markets to men. Children themselves are now users of the artificial sweetener sucralose Splenda in healthy family menus and for baking (Pena).

For their part, men play an important role in developing and marketing these substances (Pena, 2012). The chemists, salesmen and technologists in pharmaceutical, food and beverage companies were men. When the first two of these substances were accidentally discovered and developed in the 1870s and 1930s, men forged partnerships with food and beverage companies to use these substances as low-calorie sweeteners for sale to consumers. The partnerships spread to fruit canning (Pena).

General Health Issues and Artificial Sweeteners

Official position on these substances says that the choice of blend is irrelevant (Meister, 2006). The only consideration is taste or cost but all the artificial sweeteners listed by the FDA are all well-tested and found safe to use. Their consumption levels need not be limited for safety. But since they have minimal nutritional value, the health-minded should limit consumption so that these sweeteners do not replace nutritious foods, especially milk, by children and adolescents. On the other hand, their use may also improve one's nutrition if by drinking a zero-calorie diet soft drink allows him to eat or drink a more nutritious food with sufficient amount of calories. Results from 2 national diet surveys show that American adults who do so have better diets through higher vitamin and mineral intakes than those who are not on a diet and consume the equivalent foods and beverages. The effect of sugar substitutes on weight control was controversial for a while. A 1986 British study claimed that those who consumed aspartame-sweetened water increased the appetite more than those who drank plain water. But this finding was debunked by those of other studies, which suggested that the consumption of aspartame or other sugar substitutes did not increase the appetite. A Harvard Medical School study even suggested that these substitutes are helpful to those who wish to control their weight. The study participants were overweight women with similar weights during a four-month multidisciplinary weight reduction program. The women were grouped into two, one which consumed aspartame-sweetened products and another, which avoided the products. Both groups lost similar amounts of weight during the program but those in the aspartame group maintained their weight loss better than the other group, which avoided the aspartame-sweetened products (Meister).

Polyols or sugar alcohols may be used if bulk should go with the sweetness (Meister, 2006). Polyols confer 3 advantages, such as, not promoting tooth decay, a lower glycemic response, and lower calories than sugar has (Meister).

Xylitol

Two experiments were conducted on the effects of this sugar substitute (Islam, 2011). One was on non-diabetic rats and the other, on rats with type-2 diabetes. In the first, seven-week-old male Dawley rats were given xylitol feeding. The rats were divided into 3 groups: control, sucrose and xylitol groups. They wee also given rat pellet diet, generous supply of water, and sucrose solution. After 3 weeks on the diets, it was found that the rats in the xylitol group had lower body weight than the sucrose group. Weekly non-fsting blood glucose was greatly increased while fasting blood glucose was significantly decreased. The xylitol group displayed much better glucose tolerance than either of the two other groups. Results showed that xylitol may work as a better sweetener than sucrose in maintaining the diet of diabetics (Islam).

This year, a follow-up study was conducted to determine the anti-diabetic effects of xylitol on a type-2 diabetic rat model (Islam & Indrajit, 2012). It used 6-week-old male Sprague-Dawley rats, grouped into 3: for normal control, diabetic control, and xylitol. Diabetes was induced in the last 2 groups by feeding them with 10% fructose solution for 2 weeks and then by injecting streptozotocin to raise their non-fasting blood glucose level to more than 300 mg/dl. The xylitol group was given 10% xylitol solution while the first two were given ordinary drinking water only. After 5 weeks, the xylitol group had significant decreases in food and fluid intake, body weight, blood glucose, serum fructosamine and serum lipids. At the same time, there was a significant increase in this group's serum insulin concentration and glucose tolerance as compared with the diabetic control group. This finding suggests that xylitol is beneficial not only as a sugar substitute but also as a supplemental anti-diabetic food (Islam & Indrajit).

Soft Drink Consumption and Health

A meta-analysis of 88 studies found that soft drink intake produces negative health effects (Vartanian & Brownell, 2007). The studies used longitudinal and experimental methods and factors, which moderated effect sizes. Those studies funded by the food industry reported minimal effects as compared with those not industry-funded. Results of the meta-analysis showed a clear and consistent connection between soft drink intake and increased energy and body weight; lower intakes of milk, calcium, and other nutrients; and increased risk of medical problems, such as diabetes. Sweeteners are only one among the many sources of energy in a typical diet. But all alone, they can have such an impact on total energy intake. Furthermore, soft drinks displace that of important nutrients and may increase the risk of health conditions, such as diabetes. The study thus recommends decreasing soft drink consumption (Vartanian & Brownell).

Negative Effects of Sugar Substitutes on Health

Animal studies show that the consumption of too much sugar damages the teeth, increases weight, displaces nutritious foods in the diet and leads to certain degenerative diseases (Tandel, 2011). These diseases in humans include bladder cancer. A group of studies was conducted to break the controversy between the safety and risk of using these substances. These studies, however, were limited to animals and had small sample sizes, among other limitations. Replication on human subjects in the general population should be conducted to come up with more reliable findings (Tandel).

Anecdotal evidence gathered from the database of case histories suggests that the study subjects developed a number of symptoms after using the sugar substitutes (Tandel, 2011). Consequences of urbanization, sedentary lifestyles and over-consumption of sugar and fatty foods led an otherwise healthy and lean Indian population to become obese, according to one study. The Indian population was subjected to these phenomena, especially diets of saturated fats. Another study revealed obesity as the primary factor behind the spread of type-2 diabetes in India and the consequence of India's becoming the diabetic capital of the world in 2030 (Tandel).

In response to these developments, consumers urged for a wider range of low-calorie products for health maintenance (Tandel, 2011). Sugar substitutes appear to be among the answers to this call. They have fewer calories and about 200 times sweeter than natural sugar. This is clearly why the food and beverage industry has been replacing sugar or corn syrup with artificial sweeteners more and more. This endeavor costs the industry only a fraction and promises enormous profit in return (Tandel).

Health Risks with Sugar Sweetened Beverages

The rising incidence of obesity worldwide and the consequent co-morbidities, reduced quality of life and expenses incurred have sounded a serious call about sugar-sweetened beverages or SSB consumption (Malik et al., 2010). Longer studies with increasing number of participants have shown that intake of SSBs entails increased risk of type-2 diabetes mellitus and cardiovascular disease. These beverages are the biggest contributor of sugar in the diet in the U.S. And believed to increase weight partly due to incomplete compensation for liquid calories during meals. They are also a likely source and contributor of a high dietary GL and increased fructose metabolism, which leads to inflammation, insulin resistance, impaired beta-cell function and high blood pressure. At the same time, it promotes the accumulation of visceral fat and atherogenic dyslipidemia. On top of all, SSBs have little or no nutritional value. These studies, therefore, recommend limiting their intake and replacing them with health alternatives, such as water (Malik et al.).

Gender Mimorphism and Aspartame

The link established by earlier studies between aspartame consumption and impaired retention of learned behavior in rats motivated this investigation (Collison et al., 2012). It sought to investigate the effects of chronic lifetime ingestion of aspartame from the womb on changes in glucose parameters, spatial learning and memory. It used rats of both genders, using the Morris Water Maze testing to assess learning and memory and a random-fed insulin tolerance test to assess glucose levels. The male mice fed with aspartame showed weight gain, increased fasting glucose levels and reduced insulin sensitivity as compared to controlled rats. The female rats were less affected but had much higher fasting glucose levels. The male aspartame-fed mice also indicated learning impairment. The results explain that neonatal ingestion of aspartame from the diet of the pregnant mice and the newborn's exposure to dietary aspartame in the first 20 weeks from birth increased weight gain. These also increased the impairment of insulin sensitivity and cognitive performance, especially in the male rats. These results support those of earlier findings that aspartame may impair learning and memory, especially when ingested long-term or during pregnancy. In addition, hypothalamic damage has also been reported among newborn rats, which consumed large amounts of aspartame (Collison et al.).

This experiment showed that, compared with controls, newborn exposure of rats to dietary aspartame and chronic consumption in early life may impair glucose and insulin balance (Collison et al., 2012). The combination of events may also reduce cognitive performance in the newborn. Moreover, male rats showed greater sensitivity to aspartame ingestion. The study concluded that chronic exposure or use of aspartame may lead to memory deficits in newborn rats (Collison et al.).

Method

The study will be based on the data, which will be gathered from the 20,000 or so participants to enroll with the national birth cohort in Buenos Aires, Argentina in these last months of 2012. The structure of the study will still be determined. At this time, it aims at gathering this number of enrollees who live in Buenos Aires city and fluent in English in order to be recruited. Data will be obtained from the food frequency questionnaire and computer-assisted telephone interviews. The women participants will be allowed to enter the study at any number of times during the two-year study. Information will be obtained from the medical birth registry of the City on whether the deliveries will be spontaneous or medically induced.

Conclusion / Expected Results

Food additives have been described as substances, which are tested for safety for multi-purpose use. Among these are artificial sweeteners or sugar substitutes like aspartame. The American Diabetic Association has endorsed the use of aspartame and other sugar substitutes as safe. The FDA reiterated its position of endorsement despite a recent claim from the ERF complaint. The use of these substances has been popular in both sexes and in both children and adults.

Aside from these regulating bodies, separate studies endorse the use or consumption of sugar substitutes. Meister (2006) only recommends that they be consumed in appropriate amounts. Islam and Inrajit (2012) found that xylitol is even a suitable part of the treatment regimen for type-2 diabetes. But an avalanche of studies caution against the use of these sweet substances. Vartanian & Brownell (2007), Tandel (2011) and Malik et al. (2010) enumerate a list of negative health effects from their ingestion. GHR and Steiner (2012) are particular about phenylketonuria and tetrahydrobiopterin deficiency. And Collision (2012) presents evidence of the dire possibility of gender morphism from the use of aspartame in mice. This present study is likely to find a positive connection between the ingestion of sugar substitutes and preterm delivery with the substances as the causal factor.