Health benefits of Omega-7 and the potential for Macadamia s.

Transcription

1 Health benefits of Omega-7 and the potential for Macadamia s. Bianca Swanepoel & Lize Meades North-West University (Potchefstroom campus) Your logo or logos if you have more than one (edit in Slide Master)

2 BACKGROUND Desktop review on macadamia s and whether they have something unique in their nutritional composition In addition to a favourable fatty acid profile macadamias contain a number of other components that could contribute to well being. Evidence suggests that it may lower cholesterol under certain conditions. The levels of other constituents that can be gained from a reasonable amount of macadamias are too low to produce a measurable beneficial effect but they may act synergistically.

3 BACKGROUND To investigate health benefits associated with Macadamia consumption, with the focus on omega-7 palmitoleate Palmitoleic acid 16:1 n-7

4 INTRODUCTION Dietary fatty acids are often characterised by their saturation status SFA MUFA PUFA Common MUFA s are palmitoleic acid (16:1 n 7), cis-vaccenic acid (18:1 n 7) and oleic acid (18:1 n 9) Palmitoleic acid can be found as a cis (16:1c9) or a trans (16:1t9) isomer

5 Where can we find palmitoleic acid? Produced within body In food (although not common) but sources with high palmitoleate content include: macadamia nuts (17%) salmon (6%) cod liver oil (7%) and sea buckthorn (32-42%)

6 What makes palmitoleic acid so special? Circulating palmitoleate is involved in various health outcomes: obesity cardiovascular disease non-alcoholic fatty liver disease diabetes and insulin-resistance cancers

7 Obesity and palmitoleic acid The role of palmitoleic acid in obesity development is unclear Animal studies Palmitoleic acid (orally) food intake (by suppressing appetite hormones) Improved lipid profile and increased insulin sensitivity Frigolet & Gutiérrez-Aguila, 2017; Yang et al., 2013

8 Cardiovascular disease and palmitoleic acid Macadamia nuts = lipid profile, yet the n included in these groups was small and the duration short. Furthermore, it is difficult to establish the exact dose of palmitoleate given in these studies [serum lipid] and inflammation in dyslipidaemia and systemic inflammation patients, after supplementing with purified palmitoleic acid. NB! Various confounders (i.e. lifestyle and dietary factors) were not evaluated in detail as well as study was not randomized These findings contribute to the growing body of animal and epidemiological evidence on the potential CVD related health benefits of palmitoleate Hiraoka-Yamamoto et al. 2004; Garg et al. 2003; Nestel et al. 1994; Bernstein et al., 2014

9 Diabetes, insulin-resistance and palmitoleic acid Experimental models support the active metabolic benefit of palmitoleate on adipocyte, macrophage, skeletal muscle and pancreatic β-cells Large cohort study palmitoleate was associated with greater adiposity, trig. and greater insulin resistance Reasons for opposing findings??? Dimopoulos et al. 2006; Sauma et al. 2006; Maedler et al. 2003; Mozaffarian et al. 2010

10 Diabetes, insulin-resistance and palmitoleic acid Cell cultures on animal muscle cells concluded that a diet rich in palmitoleate may facilitate uptake and utilization of glucose in normal and insulin-resistant skeletal muscles. Uppsala Longitudinal Study of Adult Men reported a +correlation with palmitoleate and insulin resistance Reasons for findings: only elderly white men (limits external validity) Human cell cultures concluded in human islets, palmitoleic acid protected against the harmful effects induced by palmitic acid and against those induced by glucose In conclusion palmitoleic acid reduced onset of diabetes, should be investigated further in human studies Dimopoulos et al. 2006; Iggman et al. 2010; Maedler et al. 2003; Welters et al. 2006

11 Cancer and palmitoleic acid Limited data is available In a prospective, epidemiological design [ ] of palmitoleic acid = associated with a risk of overall and breast cancer Pouchieu et al., 2014

12 Risk associated with n-7 consumption None of the risk associations in casualties/ toxicities but rather to associations with health outcomes. The associations reported in animal studies with human metabolic diseases remains controversial. Palmitoleic acid was associated with an in breast cancer BUT ratio s is NB cis vs trans-isomer

13 Recommendations and future research Palmitoleic acid is an area of huge interest at the moment and warrants further research Urgency for a human intervention trial General study design related aspects needs to be considered and well thought through

14 Recommendations and future research 1. The way palmitoleate will be increased and administered in the diet Palmitoleic acid needs to be isolated from macadamia nuts when conducting an intervention study which will ensure that the cis-isomer is used. Experiment with different ranges of palmitoleic acid. The amount of palmitoleic acid given or intake estimation in previous studies ranged from 220mg/day to 2000mg/day. The targeted population group being investigated (i.e., insulin sensitive vs. insulin-resistant) 5. The metabolic outcomes to be measured.

15 Recommendations and future research

16 Recommendations and future research

17 Recommendations and future research Depending on the results obtained from the RCT, a controlled trail can be considered focusing on diabetic patients and the effect of palmitoleic acid. This will be a randomized controlled trail with diabetic patients and healthy controls being administrate palmitoleic acid and measuring various outcomes.

18 Recommendations and future research Large prospective, longitudinal studies where palmitoleic acid will be or was measured to try and establish an association with the health outcomes measured This will allow for health association data within SA. The results will give better insight on feasibility and also highlight which health outcome would potentially be the most important to investigate further.

19 Recommendations and future research Ball-park figure for intervention trails can be anything between R couple of million

20 Recommendations and future research 1 intervention study per year

21 Concluding remarks We cannot isolate a specific food group as a whole or even more specifically, a single nutrient as a causal ingredient to a related health outcome A combination of a balanced diet, the environment and social factors. However, palmitoleic acid should be investigated further in order to determine what role or contribution it may have within a holistic approach to health benefits in general.

22 THANK YOU!