Do consumers understand health claims on extra-virgin olive oil?

No Observed Difference in Inflammatory and Coagulation Markers Following Diets Rich in n-6 Polyunsaturated Fat vs Monounsaturated Fat in Adults With Untreated Hypercholesterolemia: A Randomized Trial

BACKGROUND

Inflammatory and prothrombotic responses are hallmark to the progression of cardiovascular disease and may be influenced by the type of dietary fat. Cottonseed oil (CSO) is rich in n-6 polyunsaturated fats and improves traditional cardiovascular disease risk factors such as cholesterol profiles. However, some clinicians are still hesitant to promote n-6 polyunsaturated fats consumption despite growing evidence suggesting they may not be independently pro-inflammatory.

OBJECTIVE

To investigate the inflammatory and coagulation marker responses to an 8-week diet intervention rich in either CSO or olive oil (OO) (OO is rich in monounsaturated fat) in adults with untreated hypercholesterolemia.

DESIGN

This was a secondary analysis of a parallel-arm randomized clinical trial with the main outcome of cholesterol measures.

PARTICIPANTS/SETTING

Participants included in this analysis were 42 sedentary adults aged 30 to 75 years (62% women) in the Athens, GA, area, between May 2018 and June 2021, with untreated hypercholesterolemia or elevated blood lipids and body mass index >18.5. Hypercholesterolemia was defined as at least two blood lipid levels in a borderline undesirable/at risk range (total cholesterol level ≥180 mg/dL, low-density lipoprotein cholesterol level ≥110 mg/dL, high-density lipoprotein cholesterol level <50 mg/dL, or triglyceride level ≥130 mg/dL), or at least one in an undesirable range (total cholesterol level ≥240 mg/dL, low-density lipoprotein cholesterol level ≥160 mg/dL, high-density lipoprotein cholesterol level <40 mg/dL, or triglyceride level ≥200 mg/dL).

INTERVENTION

Participants were randomly assigned to either the CSO or OO group in a partial outpatient feeding trial. Meals from the study provided approximately 60% of their energy needs with 30% of energy needs from either CSO or OO for 8 weeks. Participants fulfilled their remaining energy needs with meals of their choosing.

MAIN OUTCOME MEASURES

Fasting plasma concentrations of inflammatory markers, including C-reactive protein, tumor necrosis factor-α, interleukin-6, and interleukin-1β were measured at baseline and 8 weeks. Markers of coagulation potential, including plasminogen activator inhibitor-1, and tissue factor were measured at the same time points.

STATISTICAL ANALYSES PERFORMED

Repeated measures linear mixed models were used with treatment and visit in the model for analyses of all biochemical markers.

RESULTS

There were no significant differences in fasting C-reactive protein (P = 0.70), tumor necrosis factor-α (P = 0.98), interleukin-6 (P = 0.21), interleukin-1β (P = 0.13), plasminogen activator inhibitor-1 (P = 0.29), or tissue factor (P = 0.29) between groups across the intervention.

CONCLUSIONS

Inflammation and coagulation marker responses to diets rich in CSO vs OO were not significantly different between groups, and neither group showed changes in these markers in adults with untreated hypercholesterolemia. This provides additional evidence suggesting that dietary n-6 polyunsaturated fats may not promote inflammation compared with monounsaturated fatty acids, even in adults at increased risk for cardiovascular disease.

Consumers' willingness to pay for health claims during the COVID-19 pandemic: A moderated mediation analysis

The COVID-19 pandemic has posed a substantial threat to people's lives and raised health concerns. This research explores the mediating role of consumers' attitudes towards health claims in the relationship between consumers' interest in health claims and their willingness to pay (WTP) for health claims in extra virgin olive oil (EVOO). Additionally, we examine the moderation effect of COVID-19 risk perception in the relationship between consumers' interest in and attitudes towards health claims. Data were collected through an online survey in three countries: Spain, the UK and Chile. Findings confirm the mediating role of consumers' attitudes towards health claims. Furthermore, the relationship between consumers' interest and their attitudes towards health claims was stronger when COVID-19 risk perception was higher.

Effect of macronutrient fertilization on olive oil composition and quality under irrigated, intensive cultivation management

BACKGROUND

Intensive olive (Olea europaea L.) orchards are fertilized, mostly with the macronutrients nitrogen (N), phosphorus (P) and potassium (K). The effects of different application levels of these nutrients on olive oil composition and quality were studied over 6 years in a commercial intensively cultivated 'Barnea' olive orchard in Israel.

RESULTS

Oil quality and composition were affected by N, but not P or K availability. Elevated N levels increased free fatty acid content and reduced polyphenol level in the oil. Peroxide value was not affected by N, P or K levels. The relative concentrations of palmitoleic, linoleic and linolenic fatty acids increased with increasing levels of N application, whereas that of oleic acid, monounsaturated-to-polyunsaturated fatty acid ratio and oleic-to-linoleic ratio decreased.

CONCLUSION

These results indicate that intensive olive orchard fertilization should be carried out carefully, especially where N application is concerned, to avoid a decrease in oil quality due to over-fertilization. Informed application of macronutrients requires leaf and fruit analyses to establish good agricultural practices, especially in view of the expansion of olive cultivation to new agricultural regions and soils. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Blood Lipid Responses to Diets Enriched with Cottonseed Oil Compared With Olive Oil in Adults with High Cholesterol in a Randomized Trial

BACKGROUND

Increasing unsaturated fat intake is beneficial for cardiovascular health, but the type of unsaturated fat to recommend remains equivocal.

OBJECTIVES

We investigated the effects of an 8-week diet intervention that was rich in either cottonseed oil (CSO; PUFA rich) or olive oil (OO; MUFA rich) on blood lipids in hypercholesterolemic adults.

METHODS

Forty-three men and women with hypercholesterolemia (53 ± 10 years; BMI, 27.6 ± 4.8 kg/m2) completed this randomized parallel clinical trial consisting of an 8-week partial outpatient feeding intervention. Participants were given meals and snacks accounting for ∼60% of their daily energy needs, with 30% of energy needs from either CSO (n = 21) or OO (n = 22). At pre- and postdiet intervention visits, participants consumed a high-SFA meal (35% of total energy needs; 70% of energy from fat). The primary outcomes of fasting cholesterol profiles and secondary outcomes of postprandial blood lipids and glycemic markers were assessed over a 5-hour period.

RESULTS

There were greater reductions from baseline to week 8 in fasting serum total cholesterol (TC; -17.0 ± 3.94 mg/dL compared with -2.18 ± 3.72 mg/dL, respectively; P = 0.008), LDL cholesterol (-19.7 ± 3.94 mg/dL compared with -5.72 ± 4.23 mg/dL, respectively; P = 0.018), non-HDL cholesterol (-20.8 mg/dL ± 4.00 compared with -6.61 ± 4.01 mg/dL, respectively; P = 0.014), and apoB (-11.8 mg/dL ± 2.37 compared with -3.10 ± 2.99 mg/dL, respectively; P = 0.05), in CSO compared with OO. There were also visit effects from baseline to week 8 for increases in HDL cholesterol (CSO, 56.5 ± 2.79 mg/dL to 60.2 ± 3.35 mg/dL, respectively; OO: 59.7 ± 2.63 mg/dL to 64.1 ± 2.24 mg/dL, respectively; P < 0.001), and decreases in the TC:HDL-cholesterol ratio (CSO, 4.30 ± 0.27 mg/dL to 3.78 ± 0.27 mg/dL, respectively; OO, 3.94 ± 0.16 mg/dL to 3.57 ± 0.11 mg/dL, respectively; P < 0.001), regardless of group assignment. In response to the high-SFA meal, there were differences in postprandial plasma glucose (P = 0.003) and triglyceride (P = 0.004) responses and a trend in nonesterified fatty acids (P = 0.11) between groups, showing protection in the postprandial state from an occasional high-SFA fat meal with CSO, but not OO, diet enrichment.

CONCLUSIONS

CSO, but not OO, diet enrichment caused substantial improvements in fasting and postprandial blood lipids and postprandial glycemia in hypercholesterolemic adults. This trial was registered at clinicaltrials.gov as NCT04397055.