The Demise of Artificial Trans Fat: A History of a Public Health Achievement.

Policy Points This article describes a strategic combination of research, advocacy, corporate campaigns, communications, grassroots mobilization, legislation, regulatory actions, and litigation against companies and government to secure a national policy to remove artificial trans fat from the US food system. Sharing lessons we learned can help inform policymakers, academics, policy practitioners, and students across disciplines. Some of our lessons are that system change means that all consumers benefit without the need for individual behavior change; research can both identify opportunities to improve health and support policy adoption; policy efforts can serve as public education campaigns; policy campaigns can drive marketplace changes; and engaging forward-thinking companies can diffuse opposition to passing a policy. CONTEXT: For many decades, partially hydrogenated vegetable oil (PHO), the primary source of artificial trans fat in the American diet, was used widely in processed and restaurant foods. In the early 1990s, studies linked the consumption of artificial trans fat with heart disease. This article details how research and advocacy led to eliminating artificial trans fat from the US food supply. METHODS: We synthesized published studies of the health impact of trans fat, the legislative history of state and local trans fat bills, the Food and Drug Administration's (FDA) regulatory docket on trans fat labeling and its declaration that PHOs are no longer Generally Recognized as Safe (GRAS), and our own files, which included strategy documents, notes from meetings with the FDA staff, correspondence between advocates and the FDA, fact sheets, press releases, news clips, and other materials. FINDINGS: This history of trans fat provides insights into policy strategy and advocacy best practices that resulted in the removal of trans fat from food in the United States, preventing an estimated 50,000 premature deaths a year. The lessons we learned are that system change benefits all consumers without the need for individual behavior change; research can both identify opportunities to improve health through policy and support policy adoption; policy campaigns can serve as public education campaigns; policy can drive changes to products and the marketplace; and engaging forward-thinking companies can help diffuse opposition to passing a policy. Securing this policy required the persistence of scientists and health advocates in first discovering the risks and then using the science to secure policies to mitigate the identified harm. CONCLUSIONS: An understanding of the tactics used to help attain the targeted policies and how challenges were addressed (such as through communications, leveraging an expanding research base and expert reports, showing that a national policy was feasible through voluntary corporate changes and state and local policy, and litigation against companies and government agencies) may provide a model for scientists, students, advocates, and policymakers. We hope this account will inform efforts to address other public health challenges, such as the current threats of excessive exposure to sodium and added sugars, which persist in the US food system.

A Meta-Analysis of Food Labeling Effects on Consumer Diet Behaviors and Industry Practices.

CONTEXT: The influence of food and beverage labeling (food labeling) on consumer behaviors, industry responses, and health outcomes is not well established. EVIDENCE ACQUISITION: PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed. Ten databases were searched in 2014 for studies published after 1990 evaluating food labeling and consumer purchases/orders, intakes, metabolic risk factors, and industry responses. Data extractions were performed independently and in duplicate. Studies were pooled using inverse-variance random effects meta-analysis. Heterogeneity was explored with I2, stratified analyses, and meta-regression; and publication bias was assessed with funnel plots, Begg's tests, and Egger's tests. Analyses were completed in 2017. EVIDENCE SYNTHESIS: From 6,232 articles, a total of 60 studies were identified, including 2 million observations across 111 intervention arms in 11 countries. Food labeling decreased consumer intakes of energy by 6.6% (95% CI= -8.8%, -4.4%, n=31), total fat by 10.6% (95% CI= -17.7%, -3.5%, n=13), and other unhealthy dietary options by 13.0% (95% CI= -25.7%, -0.2%, n=16), while increasing vegetable consumption by 13.5% (95% CI=2.4%, 24.6%, n=5). Evaluating industry responses, labeling decreased product contents of sodium by 8.9% (95% CI= -17.3%, -0.6%, n=4) and artificial trans fat by 64.3% (95% CI= -91.1%, -37.5%, n=3). No significant heterogeneity was identified by label placement or type, duration, labeled product, region, population, voluntary or legislative approaches, combined intervention components, study design, or quality. Evidence for publication bias was not identified. CONCLUSIONS: From reviewing 60 intervention studies, food labeling reduces consumer dietary intake of selected nutrients and influences industry practices to reduce product contents of sodium and artificial trans fat.

Impact on the physical and sensory properties of salt-and fat-reduced traditional Irish breakfast sausages on various age cohorts acceptance.

The properties of varying salt and fat levels in traditional breakfast sausages were investigated. Sausages were produced with fat levels of: 30%, 20% and 15%. Fat was replaced with pea extract. Salt levels employed were: 2.5%, 1.1% and 0.0%. A reduced sodium salt which contains 45% less sodium than standard salt was used. Sensory analysis was conducted on consumers (n = 228): 18-40 yrs., 41-64 yrs. and 65-85 yrs. The 18-40 yr. olds preferred sausages containing 20% fat, 41-64 yr. olds preferred sausages with 15% fat, 65+ age group preferred sausages containing 30% fat. The 18-40 yr. olds preferred high salt samples, 41-64 yr. olds displayed no salt preference, while the 65+ age group preferred high salt sausages. Sausage formulation choice was found to be driven by texture for the younger age cohort, flavour for the middle age cohort and visual aspects from the oldest age cohort. There is a need to understand how meat products might be reformulated different age palates.

Denmark's Policy on Artificial Trans Fat and Cardiovascular Disease.

INTRODUCTION: The consumption of trans fat is associated with cardiovascular disease (CVD). In January 2004, Denmark became the first country in the world to regulate the content of artificial trans fat in certain ingredients in food products, which nearly eliminated artificial trans fat from the Danish food supply. The goal of this study was to assess whether Denmark's trans fat policy reduced deaths caused by CVD. METHODS: Annual mortality rates in Organisation for Economic Co-operation and Development (OECD) countries from 1990 to 2012 were used to estimate the effect of Denmark's food policy on CVD mortality rates. Synthetic control methods were employed to simulate the CVD mortality trajectory that Denmark would have witnessed in the absence of the policy and to measure the policy's impact on CVD mortality rates. Analyses were conducted in 2015. RESULTS: Before the trans fat policy was implemented, CVD mortality rates in Denmark closely tracked those of a weighted average of other OECD countries (i.e., the synthetic control group). In the years before the policy, the annual mean was 441.5 deaths per 100,000 people in Denmark and 442.7 in the synthetic control group. In the 3 years after the policy was implemented, mortality attributable to CVD decreased on average by about 14.2 deaths per 100,000 people per year in Denmark relative to the synthetic control group. CONCLUSIONS: Denmark's food policy, which restricted the content of artificial trans fat in certain ingredients in its food supply, has been followed by a decrease in CVD mortality rates.

Tolerance of rising dietary concentrations of esterified propoxylated glycerol (EPG) among human volunteers.

A solid form of esterified propoxylated glycerol (EPG) was administered to 16 healthy male volunteers in butter-like spread and baked goods, resulting in intakes that rose in 30-g increments from 30 to 150 g; each level was administered on a single day, followed by a 2-day washout period. Elevated serum transaminase (ALT and/or AST) and lower HDL cholesterol levels were noted at 60 g and greater, possibly related to changes in the diet (high-carbohydrate and increasingly low-fat), rather than to EPG itself. There was no apparent association between EPG consumption and adverse effects reported. In general, EPG had no effect on bowel function, except in a single subject, who reported increased frequency of movements during the 2 days that followed consumption of 150 g EPG. All abnormal values returned to normal after the study, and subjects were otherwise asymptomatic. Accordingly, the effects on transaminase and HDL levels observed in this study were considered possibly adaptive and not clinically significant. Experimental animal studies, including lifetime studies, had shown no effects on these parameters. More importantly, the effect was associated with intakes of 60-150 g EPG, which exceeds the approximate intake of 20 g/day or less expected from currently intended commercial food uses.

Assessment of the effect of esterified propoxylated glycerol (EPG) on the status of fat-soluble vitamins and select water-soluble nutrients following dietary administration to humans for 8 weeks.

This double-blind, randomized, controlled study assessed the effect of esterified propoxylated glycerol (EPG) on fat-soluble vitamins and select nutrients in human subjects. For 8 weeks, 139 healthy volunteers consumed a core diet providing adequate caloric and nutrient intakes. The diet included items (spread, muffins, cookies, and biscuits) providing EPG (10, 25, and 40 g/day) vs. margarine alone (control). EPG did not significantly affect circulating retinol, α-tocopherol, or 25-OH D2, but circulating ß-carotene and phylloquinone were lower in the EPG groups, and PIVKA-II levels were higher; 25-OH D3 increased but to a lesser extent than the control. The effect might be related to EPG acting as a lipid "sink" during gastrointestinal transit. No effects were seen in secondary endpoint measures (physical exam, clinical pathology, serum folate, RBC folate, vitamin B12, zinc, iron, calcium, phosphorus, osteocalcin, RBP, intact PTH, PT, PTT, cholesterol, HDL-C, LDL-C, triglycerides). Gastrointestinal adverse events (gas with discharge; diarrhea; oily spotting; oily evacuation; oily stool; liquid stool; soft stool) were reported more frequently by subjects receiving 25 or 40 g/day of EPG. In general, the incidence and duration of these symptoms correlated directly with EPG dietary concentration. The results suggest 10 g/day of EPG was reasonably well tolerated.

Enriched n-3 PUFA/konjac gel low-fat pork liver pâté: lipid oxidation, microbiological properties and biogenic amine formation during chilling storage.

Low-fat pork liver pâtés enriched with n-3 PUFA/konjac gel were formulated by replacing (totally or partially) pork backfat by a combination of healthier oils (olive, linseed and fish oils) and konjac gel. Lipid oxidation, microbiological changes and biogenic amine (BA) formation were studied in healthier-lipid pâtés during chill storage (85 days, 2 °C). Increasing unsaturated fatty acid levels favoured lipid oxidation, although the levels reached were low throughout the storage period, ranging from 0.113 to 0.343 mg malonaldehyde/kg sample. Neither the formulation nor the time in storage affected the microbial load. Biogenic amine contents of products (the sum of initial concentrations and amines formed during storage) varied according to the type of BA but were far below levels that could constitute a consumer health hazard.

Effects of margarines and butter consumption on lipid profiles, inflammation markers and lipid transfer to HDL particles in free-living subjects with the metabolic syndrome.

OBJECTIVE: Our purpose was to examine the effects of daily servings of butter, no-trans-fat margarine and plant sterol margarine, within recommended amounts, on plasma lipids, apolipoproteins (Apos), biomarkers of inflammation and endothelial dysfunction, and on the transfer of lipids to HDL particles in free-living subjects with the metabolic syndrome. METHODS: This was a randomized, single-blind study where 53 metabolic syndrome subjects (62% women, mean age 54 years) received isocaloric servings of butter, no-trans-fat margarine or plant sterol margarine in addition to their usual diets for 5 weeks. The main outcome measures were plasma lipids, Apo, inflammatory and endothelial dysfunction markers (CRP, IL-6, CD40L or E-selectin), small dense LDL cholesterol concentrations and in vitro radioactive lipid transfer from cholesterol-rich emulsions to HDL. Difference among groups was evaluated by analysis of variance. RESULTS: There was a significant reduction in Apo-B (-10.4 %, P=0.043) and in the Apo-B/Apo-A-1 ratio (-11.1%, P=0.034) with plant sterol margarine. No changes in plasma lipids were noticed with butter and no-trans-fat margarine. Transfer rates of lipids to HDL were reduced in the no-trans-fat margarine group: triglycerides -42.0%, (P<0.001 vs butter and sterol margarine) and free cholesterol -16.2% (P=0.006 vs sterol margarine). No significant effects were noted on the concentrations of inflammatory and endothelial dysfunction markers among the groups. CONCLUSIONS: In free-living subjects with the metabolic syndrome consumption of plant sterol and no-trans-fat margarines within recommended amounts reduced, respectively, Apo-B concentrations and the ability of HDL to accept lipids.

Olestra is associated with slight reductions in serum carotenoids but does not markedly influence serum fat-soluble vitamin concentrations.

BACKGROUND: The 1996 Food and Drug Administration approval of the fat substitute olestra (sucrose polyester) called for active postmarketing surveillance because preapproval studies showed that olestra may lower circulating concentrations of fat-soluble nutrients such as vitamins and carotenoids. OBJECTIVE: The objective of the Olestra Post-Marketing Surveillance Study was to examine whether customary consumption of olestra-containing savory snacks was associated with changes in serum fat-soluble vitamin and carotenoid concentrations among free-living persons in geographically and ethnically distinct US cities. DESIGN: Adults (n = 2535) and their children aged 12-17 y (n = 272) in Baltimore, Minneapolis, and San Diego attended clinic visits during which data were collected on diet, savory snack consumption, lifestyle, and anthropometric indexes. Blood samples were drawn to assay carotenoids and vitamins A, D, E, and K. Data and blood samples were collected both before and after the nationwide introduction of olestra. General estimating equations were used in multivariate-adjusted models that examined olestra's association with the specified serum nutrients. RESULTS: Compared with no intake, the top 2 tertiles of olestra use in adults were associated with circulating carotenoid concentrations that were modestly but significantly lower (4.3% to 22.4%). There were no significant associations of olestra with any serum nutrients among adolescents. CONCLUSIONS: This active postmarketing surveillance study of a food additive suggests that small decreases in serum fat-soluble nutrients are attributable to olestra use. Although health outcomes were not measured here, it is unlikely that these small changes in nutrient measures would adversely affect health.

Daily intake of multivitamins during long-term intake of olestra in men prevents declines in serum vitamins A and E but not carotenoids.

The objective of this study was to determine whether vitamin supplementation during long-term (36 wk) ingestion of olestra supplemented with vitamin E could prevent decreases in vitamin E, vitamin A, and carotenoids. This was a 36-wk study of 37 healthy males randomly assigned to consume a control diet composed of 33% energy from fat, a similar diet in which one third of the energy from fat had been replaced with olestra, or a fat-reduced (25% of energy from fat) diet. Subjects also ingested a daily multivitamin (Centrum). Serum concentrations of alpha-tocopherol, retinol, beta-carotene, lycopene, and lutein + zeaxanthin were analyzed by HPLC. Subjects eating the olestra-containing diet had substantial decreases in serum beta-carotene, lycopene, and lutein + zeaxanthin, which occurred by 12 wk; these changes were found despite correcting for serum total cholesterol or BMI. Serum beta-carotene and lycopene concentrations were below the lower limit of the reference range (<0.186 and <0.298 mumol/L, respectively) at one or more time points. The slight decline in serum alpha-tocopherol concentration, significant at 24 wk, was caused by the decline in serum cholesterol. Retinol concentrations decreased with time in all 3 groups, but were not affected by olestra. We conclude that supplementation with a multivitamin containing vitamins A and E was adequate to prevent olestra-induced decrease in serum alpha-tocopherol and retinol. Olestra-induced decreases in serum beta-carotene, lycopene, and lutein + zeaxanthin were not prevented by the vitamin supplement used in this study.

Phytosterol additives increase blood pressure and promote stroke onset in salt-loaded stroke-prone spontaneously hypertensive rats.

1. To assess the effect of dietary phytosterol on stroke and the lifespan of salt-loaded stroke-prone spontaneously hypertensive rats (SHRSP), we investigated the effects of the addition of phytosterol to soybean oil (phytosterol content: 0.3%) on stroke onset, lifespan following onset of stroke and overall lifespan compared with canola oil (phytosterol content: 0.9%). 2. Six-week-old male SHRSP were fed a test diet prepared by the addition of canola oil (CA diet), soybean oil (SO diet), soybean oil plus 0.6% phytosterol (SO + 0.06P diet) or soybean oil plus 4.5% phytosterol (SO + 0.45P diet) as a 10% fat source. 3. Systolic blood pressure (SBP) increased in the SO + 0.06P and SO + 0.45P groups compared with the SO group and the increase was dependent on the amount of phytosterol added, indicating that the addition of phytosterol to soybean oil may promote an increase in SBP in salt-loaded SHRSP. 4. The onset of stroke was shortest in the SO + 0.45P group and survival after the onset of stroke was shortest in the CA group. Consequently, the SO + 0.45P and CA groups showed marked lifespan shortening, indicating that a fivefold greater amount of phytosterol was required to produce an effect equivalent to that of canola oil. 5. Investigation of the mRNA expression of ATP-binding cassette (ABC) transporters involved in intestinal phytosterol absorption indicated significant decreases in the intestinal mRNA expression of Abcg5 and Abcg8 in SHRSP and Wistar-Kyoto rats compared with Wistar rats. 6. In conclusion, the addition of phytosterol to soybean oil elevated SBP and promoted the onset of stroke, which may cause a reduction in survival time. However, a fivefold greater amount of phytosterol was required to produce an effect that was equivalent to the survival time-shortening effect of canola oil. The significant decrease in the intestinal mRNA expression of Abcg5 and Abcg8 in SHRSP may be responsible, at least in part, for the unfavourable effects observed following the addition of phytosterol.

Authors' financial relationships with the food and beverage industry and their published positions on the fat substitute olestra.

OBJECTIVES: This study examined the association between authors' published positions on the safety and efficacy in assisting with weight loss of the Procter & Gamble (P&G) fat substitute olestra and their financial relationships with the food and beverage industry. METHODS: Journal articles about olestra, and their authors, were classified as supportive, critical, or neutral with respect to its use. Authors not known to have industry affiliations were surveyed about their financial relationships. RESULTS: Supportive authors were significantly more likely than critical or neutral authors to have financial relationships with P&G (80% vs 11% and 21%, respectively; P <.0001). All authors disclosing an affiliation with P&G were supportive. CONCLUSIONS: Because authors' published opinions were associated with their financial relationships, obtaining noncommercial funding may be more essential to maintaining objectivity than disclosing personal financial interests.

Additive gastrointestinal effects with concomitant use of olestra and orlistat.

OBJECTIVE: To report a case of significant additive gastrointestinal effects with concomitant use of orlistat and an olestra-containing snack food. CASE SUMMARY: A 16-year-old African American girl with type 2 diabetes, hypercholesterolemia, and hypertension was participating in a pilot study that tested the safety and efficacy of orlistat. After 2 weeks of orlistat treatment, the patient presented to the clinic with complaints of soft, fatty/oily stools, flatus with discharge, abdominal pain, increased flatus, and fecal incontinence. On further questioning, it was determined that she was also consuming approximately 5 ounces of olestra-containing potato chips on a daily basis. The patient eliminated olestra from her diet and returned to the clinic with substantially diminished gastrointestinal adverse effects, despite continuing to take orlistat. DISCUSSION: This is the first published case describing additive gastrointestinal effects after concurrent use of orlistat and olestra. Education about the potential for serious additive gastrointestinal adverse effects is important to prevent premature and unnecessary discontinuation of orlistat therapy. Awareness of this potential interaction could be especially important for patients with underlying disease states in which severe gastrointestinal symptoms could result in significant complications. CONCLUSIONS: This case illustrates that significant gastrointestinal distress may result after olestra consumption during orlistat therapy. All patients receiving orlistat for the management of obesity should be properly educated about this potential drug-food interaction.

Randomized, double-blind, placebo-controlled, food allergy challenge to olestra snacks.

Following approval of the fat replacer olestra for use in preparing savory snacks, Procter & Gamble implemented a postmarketing surveillance program to monitor marketplace introduction. Three and one-half percent of all health effects reported by consumers to the surveillance toll-free number were allergy-type symptoms (e.g., rash, itching, edema, hives, dyspnea). Because of these reports, we investigated whether olestra or some component of olestra snacks was a likely allergen in some subset of the population. A single center, randomized, double-blind, placebo-controlled, within-subject crossover food challenge study was conducted to confirm or refute the allergenicity of olestra snacks. Of the 65 subjects who reported symptoms consistent with immediate hypersensitivity to olestra's postmarketing surveillance program, 14 men and women traveled to the Arkansas Children's Hospital Research Institute to participate in this study. Each subject underwent a standard skin prick test at the beginning of the study, to help determine what component, if any, of the olestra product was allergenic. Following the skin prick test, subjects ate in random order, olestra-containing potato chips and regular fat-containing potato chips. The dose of potato chips consumed at each challenge was at least the amount alleged to have caused the symptoms that prompted the consumer to phone the postmarketing surveillance toll-free number. No subject experienced an allergic reaction after consuming the olestra-containing chips. Nor did any subject elicit a positive response to olestra following the skin prick testing. Two subjects had positive reactions consistent with immediate hypersensitivity after consuming the regular-fat, placebo potato chips. The results of this study confirm that olestra is unlikely to have an allergenic potential.

Postmarketing surveillance of new food ingredients: design and implementation of the program for the fat replacer olestra.

Following U.S. Food and Drug Administration (FDA) approval for the use of olestra, a noncaloric fat substitute (brand name Olean) in food snacks, the manufacturer agreed to provide safety updates on market experience to the FDA. However, guidelines for food product postmarketing surveillance (PMS) are not available and those typically used with medical products were only partly applicable. In modeling the Olean program, we drew from experience with consumer products and incorporated elements typical of medical product PMS. A cooperative effort was established with Olean snack manufacturers and a two-tiered, multidisciplinary approach enlisting Consumer Relations and Medical Affairs personnel was used to maximize use of specialized skills. The result of this effort was implementation of a reliable PMS system which could handle a high volume of reports from consumers while providing pertinent data required for medical interpretation of these reports. Summaries of data for the Olean snack manufacturers and FDA were generated in timely fashion. In addition to collection of the spontaneous reports from consumers, a clinical studies program was undertaken and an independent medical advisory panel was established. Through these, we gained perspective on the spontaneous reports and additional confirmation of the safety of olestra in savory snacks.

Postmarketing surveillance of new food ingredients: results from the program with the fat replacer olestra.

Market introduction of savory snacks containing olestra offered an opportunity to evaluate the safety of olestra in a free-living population and thereby compare the outcome to the previously established safety profile determined in clinical trials in which subjects were required to eat predetermined amounts at prescribed intervals. Therefore, a multifaceted postmarketing surveillance program was designed to evaluate consumer experience and safety of olestra in the marketplace. Customer comments were solicited through toll-free telephone numbers. Collected data were evaluated by both internal and external medical experts. About 10% of toll-free telephone calls reported health effects, most of which were gastrointestinal (GI) in nature. Clinical studies were designed and conducted to determine potential GI effects under the range of consumption patterns reported by toll-free calls. Health effects reported were those found commonly in the general population and analyses of the data found no biological reason to conclude that serious or meaningful health effects were the result of olestra consumption.

Effects of olestra and sorbitol consumption on objective measures of diarrhea: impact of stool viscosity on common gastrointestinal symptoms.

The aim of this study was to determine the effects of olestra and sorbitol consumption on three accepted objective measures of diarrhea (stool output >250 g/day, liquid/watery stools, bowel movement frequency >3/day), and how stool composition influences reports of common gastrointestinal symptoms. A double-blind, placebo-controlled study compared the effects of sorbitol (40 g/day in candy), a poorly absorbed sugar-alcohol with known osmotic effects, with those of olestra (20 or 40 g/day in potato chips), a nonabsorbed fat, on objective measures of stool composition and GI symptoms. Sixty-six subjects resided on a metabolic ward for 12 days: 2 days lead-in, 4 days baseline, 6 days treatment. Sorbitol 40 g/day resulted in loose/liquid stools within 1-3 h of consumption. In contrast, olestra resulted in a dose-responsive stool softening effect after 2-4 days of consumption. Subjects reported "diarrhea" when mean stool apparent viscosity (peak force (PF), g) decreased from a perceived "normal" (mean +/- SE, 1355 +/- 224 g PF; firm stool) to loose (260 +/- 68 g PF) stool. Mean apparent viscosity of stool during treatment: placebo, 1363 +/- 280 g (firm); olestra 20 g/day 743 +/- 65 g (soft); olestra 40 g/day, 563 +/- 105 g (soft); and sorbitol 40 g/day, 249 +/- 53 g (loose). Of the 1098 stool samples collected, 38% (419/1098) were rated by subjects as "diarrhea," yet only 2% of treatment days (all in the sorbitol treatment group) met commonly accepted criteria for a clinical diarrhea. Sorbitol, but not olestra, increased the severity of abdominal cramping, urgency and nausea compared to placebo. Olestra consumption, at levels far in excess of normal snacking conditions, resulted in a gradual stool softening effect after several days of consumption, did not meet any of the three objective measures of diarrhea, and did not increase GI symptoms. Sorbitol consumption, at only 80% of the dose requiring a "laxative effect" information label, resulted in rapid onset loose/liquid stools and a significant increase in abdominal cramping, urgency and nausea. Overall, subjects categorized stool as "diarrhea" when stool decreased from their perceived "normal," but the vast majority of these reports were not associated with clinically significant diarrhea.

Effect of the moderate consumption of olestra in patients receiving long-term warfarin therapy.

We conducted a prospective, randomized, double-blind, placebo-controlled, parallel-group trial to evaluate the effect of the moderate consumption of snacks containing olestra on the international normalized ratio (INR) in 40 patients receiving long-term warfarin therapy. Patients continued their warfarin regimen and were assigned to receive 1.5 servings/day (42 g) for 2 weeks of Pringles Original Flavor Fat Free Potato Crisps with Olean (12 g olestra/1.5 servings) or Pringles Original Flavor Potato Crisps (placebo group). Patients' INRs were measured weekly for 2 weeks. Thirty-six patients completed the first week of the trial. After 1 week, the mean change in the INR from baseline increased by 0.02 +/- 0.5 in the olestra group and by 0.17 +/-0.4 in the placebo group (p= 0.327). Ten patients in the olestra group and 12 in the placebo group completed the second week of the study. Mean change in the INR from baseline was similar at week 2, -0.18 +/- 0.38 and 0.09 +/- 0.53 (p=0.193), respectively. Gastrointestinal side effects (diarrhea, gas, bloating) occurred in three patients in the olestra group and five in the placebo group (p=0.3). Moderate consumption of snacks containing olestra did not significantly affect the INR (> 0.3 U) at 1 week in patients receiving long-term anticoagulation with warfarin. It does not appear that moderate consumption of these snacks would affect the INR after 2 weeks, but this must be confirmed in a larger sample with adequate power at 2 weeks.