Volume 51, Issue 5, May 2022

Non-fasting lipids: A change in practice

Tim Tse    Bosco Wu    Simon Willcock    Sanjyot Vagholkar   
doi: 10.31128/AJGP-10-21-6194   |    Download article
Cite this article    BIBTEX    REFER    RIS

Over the past decade, multiple guidelines by cardiovascular societies around the world have advised that testing for non-fasting lipids be recommended in preference to fasting lipids to assess for cardiovascular risk.1–4 However, Australia’s most recent guideline on cardiovascular risk was published in 2012 prior to the aforementioned worldwide changes and continues to suggest the use of a fasting lipid profile to assess absolute cardiovascular risk.5 Australian general practitioners (GPs) and their patients may not be aware of this global paradigm shift in testing, which has significant benefits to the patient, doctor and society. Indeed, one could argue that the non-fasting state is more representative of cardiovascular risk, as humans spend most time in the postprandial condition. We highlight below current recommendations from around the world and the rationale for shifting from fasting to non-fasting.

There are economic and clinical reasons why testing for non-fasting lipids is superior to fasting lipids. First, there is benefit to the patient by not having to take time out of their schedule expending resources to return on another day after fasting. This also relieves the strain on pathology collection centres in the morning, where it is common to see multiple patients having to wait for extended periods compared to other times due to the fasting testing surge. Second, avoiding unnecessary testing of fasting lipids reduces the risk of symptomatic hypoglycaemia in individuals with diabetes. Third, doctors will find it easier to manage clinical risk and workflow, with fewer patients being lost to follow-up because they are more likely to have tests performed on the same day, increasing compliance. This is especially relevant given that pathology collection services are often co-located in general practice clinics.1,6

An argument for the use of fasting lipids is that plasma triglycerides increase following a fat tolerance test. As low-density lipoprotein cholesterol (LDL-C) is commonly estimated by the Friedelwald equation, which is total cholesterol subtracted by high-density lipoprotein cholesterol (HDL-C) subtracted by triglycerides/2.2 mmol/L. Subsequently, an elevated triglyceride level could lead to an underestimation of LDL-C levels.7,8 Despite this concern, normal food intake has been shown to increase triglyceride and cholesterol levels at a much lower rate than a fat tolerance test, and is considered clinically insignificant. A study of 92,285 individuals from the general population in Denmark recruited from 2003 to 2014 evaluated the maximal mean change of lipids at 1–6 hours following normal food intake. It demonstrated an increase of triglycerides by 0.3 mmol/L, total cholesterol decreased by 0.2 mmol/L, LDL-C decreased by 0.2 mmol/L, and there was no change in HDL-C.1 Patients found to have elevated triglycerides from non-fasting lipids may warrant a subsequent fasting sample for calculation of LDL-C and triglyceride levels.

Another reported concern with using non-fasting lipids is that they cannot be used for management decisions because previous studies used fasting lipids in their protocols. However, a meta-analysis of 68 long-term prospective studies of more than 300,000 patients found there was no significant difference in using non-fasting lipids compared to fasting lipids for vascular risk assessment. It further concluded that only total and HDL-C cholesterol levels, known to have nonsignificant variations due to fasting, are required for the assessment of cardiovascular risk.9 In addition, a further three large statin trials with more than 43,000 patients have used non-fasting lipids to assess and manage cardiovascular disease.1 A recent randomised controlled trial of 8270 patients was the first to measure fasting and non-fasting lipids in the same individual at baseline and found no difference in risk prediction of future coronary or atherosclerotic cardiovascular events.10

Table 1 summarises current published consensus statements regarding non-fasting lipid testing. The Canadian Cardiovascular Society, the European Atherosclerosis Society, the European Federation of Clinical Chemistry and Laboratory Medicine and the National Institute of Health Care and Excellence all recommend non-fasting lipids with a repeat of fasting lipids only if initial triglycerides are above 4.5 mmol/L, 5 mmol/L or 10 mmol/L, respectively.1,2,4 The American College of Cardiology/American Heart Association Task Force recommends either non-fasting or fasting lipids with a repeat of fasting lipids only if non-fasting triglycerides are >4.5 mmol/L.3  


Table 1. Summary of international guidelines for non-fasting lipid testing
Guideline Year Recommendation
Canadian Cardiovascular Society2 2021
  • Non-fasting lipids recommended
  • Fasting lipids if individuals with known triglyceride levels >4.5 mmol/L
American College of Cardiology/American Heart Association Task Force3 2018
  • Non-fasting lipids or fasting lipids for adults not on lipid-lowering therapy
  • If non-fasting plasma triglycerides >4.5 mmol/L, repeat in fasting state
  • Adults with a family history of premature atherosclerotic cardiovascular disease (ASCVD) or genetic hyperlipidaemia should have fasting lipids
European Atherosclerosis Society/European Federation of Clinical Chemistry and Laboratory Medicine1 2016
  • Non-fasting lipids recommended
  • If non-fasting plasma triglycerides >5.0 mmol/L, repeat in fasting state
National Clinical Guideline Centre (NICE)/Joint British Societies Guidelines4 2014
  • Non-fasting lipids are recommended
  • If non-fasting plasma triglycerides ≥10.0 mmol/L, repeat in fasting state
  • Adults suspected of familial hypercholesterolaemia can have a subsequent fasting sample

Non-fasting lipid testing is now recommended throughout the world. The clinical and economic benefits to individuals and society are not insignificant, especially with everyday lives becoming more complex. As GPs, it is important that we educate patients and other health providers that there is no reason why non-fasting lipids should not become the norm. The early morning queue for fasting lipids at pathology collection sites might then become a relic of the past.

Competing interests: None.
Provenance and peer review: Not commissioned, externally peer reviewed.
Funding: None.
Correspondence to:
This event attracts CPD points and can be self recorded

Did you know you can now log your CPD with a click of a button?

Create Quick log
  1. Nordestgaard BG, Langsted A, Mora S, et al; European Atherosclerosis Society (EAS) and the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) joint consensus initiative. Fasting is not routinely required for determination of a lipid profile: Clinical and laboratory implications including flagging at desirable concentration cut-points – A joint consensus statement from the European Atherosclerosis Society and European Federation of Clinical Chemistry and Laboratory Medicine. Eur Heart J 2016;37(25):1944–58. doi: 10.1093/eurheartj/ehw152. Search PubMed
  2. Pearson GJ, Thanassoulis G, Anderson TJ, et al. 2021 Canadian Cardiovascular Society guidelines for the management of dyslipidemia for the prevention of cardiovascular disease in adults. Can J Cardiol 2021;37(8):1129–50. doi: 10.1016/j.cjca.2021.03.016. Search PubMed
  3. Grundy SM, Stone NJ, Bailey AL, et al. 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA guideline on the management of blood cholesterol: Executive summary: A report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol 2019;73(24):3168–209. doi: 10.1016/j.jacc.2018.11.002. Search PubMed
  4. JBS3 Board. Joint British Societies’ consensus recommendations for the prevention of cardiovascular disease (JBS3). Heart 2014;100 Suppl 2:ii1–ii67. doi: 10.1136/heartjnl-2014-305693. Search PubMed
  5. National Vascular Disease Prevention Alliance. Guidelines for the management of absolute cardiovascular disease risk. Melbourne, Vic: National Stroke Foundation, 2012. Search PubMed
  6. Langsted A, Nordestgaard BG. Nonfasting versus fasting lipid profile for cardiovascular risk prediction. Pathology 2019;51(2):131–41. doi: 10.1016/j.pathol.2018.09.062. Search PubMed
  7. Rifai N, Merrill JR, Holly RG. Postprandial effect of a high fat meal on plasma lipid, lipoprotein cholesterol and apolipoprotein measurements. Ann Clin Biochem 1990;27(Pt 5):489–93. doi: 10.1177/000456329002700512. Search PubMed
  8. Rahman F, Blumenthal RS, Jones SR, Martin SS, Gluckman TJ, Whelton SP. Fasting or non-fasting lipids for atherosclerotic cardiovascular disease risk assessment and treatment? Curr Atheroscler Rep 2018;20(3):14. doi: 10.1007/s11883-018-0713-2. Search PubMed
  9. Di Angelantonio E, Sarwar N, Perry P, et al. Major lipids, apolipoproteins, and risk of vascular disease. JAMA 2009;302(18):1993–2000. doi: 10.1001/jama.2009.1619. Search PubMed
  10. Mora S, Chang CL, Moorthy MV, Sever PS. Association of nonfasting vs fasting lipid levels with risk of major coronary events in the Anglo-Scandinavian cardiac outcomes trial-lipid lowering arm. JAMA Intern Med 2019;179(7):898–905. doi: 10.1001/jamainternmed.2019.0392. Search PubMed

LipidsPathology tests

Download article