Summary
There is a large amount of controversy relating dietary fat intake and coronary artery
disease. It has been strongly suggested that saturated fat is not harmful and that
polyunsaturated fat is either not beneficial or even harmful. Given that dietary lipids
and fibre can influence serum lipids which are strongly linked to the risk of coronary
artery disease I have reviewed recent evidence linking diet and serum lipids to confirm
a diet-heart disease link. Over 84 studies have been included in a recent meta-analysis
and meta-regression which examined the effects of changes in fat type on lipid levels.
An absolute 1% reduction in saturated fat or trans fat intake as a percentage of energy
with replacement by n-6 polyunsaturated fat would lead to a reduction in low density
lipoprotein (LDL) cholesterol of 0.05 mmol/L. In most Western countries the difference
in intake between the highest quintile and the lowest quintile of saturated fat is
about 7%, so moving from the highest to the lowest quintile should lower LDL cholesterol
by 0.35 mmol/L or about 10%. This change should lower cardiovascular disease rates
by at least 10%. Replacing this amount of saturated fat with carbohydrate of average
quality would lower LDL cholesterol by 0.21 mmol/L and increase fasting triglyceride
by 0.17 mmol/L. This combination of effects would have a neutral effect on cardiovascular
disease rates. However, replacement of trans fat appears to reduce disease rates and
total mortality. Substituting low glycaemic index carbohydrates for high glycaemic
index carbohydrates will lower triglyceride by 15–25% and reduce cardiovascular risk.
Large doses of fish oil will lower triglyceride with a mean lowering of 0.45 mmol/L
for a 3.5 g/day amount. Large doses of soluble fibre (3.5–7.0 g/day) lower LDL cholesterol
by 0.2–0.35 mmol/L with Konjac glucomannan being the most effective per gram. Plant
sterols or stanols lower LDL cholesterol by about 10% for a 2 g/day dose, while exercise
and weight loss lower cardiovascular risk predominantly by lowering fasting triglyceride.
In conclusion, diet lowers LDL cholesterol and triglyceride and dietary changes should
be ultimately linked to a reduced risk of heart disease.
Key words
Abbreviations:
BMI (body mass index), CHO (carbohydrate), CVD (cardiovascular disease), HDL (high density lipoprotein), LDL (low density lipoprotein), Lp(a) (lipoprotein (a)), VLDL (very low density lipoprotein)To read this article in full you will need to make a payment
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References
- Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins: a meta-analysis of 60 controlled trials.Am J Clin Nutr. 2003; 77: 1146-1155
- Effects of Saturated Fatty Acids on Serum Lipids and Lipoproteins: A Systematic Review and Regression Analysis.World Health Organisation, Geneva2016
- PCSK9 loss-of-function variants, low-density lipoprotein cholesterol, and risk of coronary heart disease and stroke: data from 9 studies of blacks and whites.Circ Cardiovasc Genet. 2017; 104e001632
- Lifelong reduction of LDL-cholesterol related to a common variant in the LDL-receptor gene decreases the risk of coronary artery disease – a Mendelian Randomisation study.PLoS One. 2008; 3e2986
- Association between lowering LDL-C and cardiovascular risk reduction among different therapeutic interventions: a systematic review and meta-analysis.JAMA. 2016; 316: 1289-1297
- Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease.Am J Clin Nutr. 2010; 91: 535-546
- Association of dietary, circulating, and supplement fatty acids with coronary risk: a systematic review and meta-analysis.Ann Intern Med. 2014; 160: 398-406
- Intake of saturated and trans unsaturated fatty acids and risk of all cause mortality, cardiovascular disease, and type 2 diabetes: systematic review and meta-analysis of observational studies.BMJ. 2015; 351: h3978
- Saturated fats compared with unsaturated fats and sources of carbohydrates in relation to risk of coronary heart disease: a prospective cohort study.J Am Coll Cardiol. 2015; 66: 1538-1548
- Association of specific dietary fats with total and cause-specific mortality.JAMA Intern Med. 2016; 176: 1134-1145
- Reduction in saturated fat intake for cardiovascular disease.Cochrane Database Syst Rev. 2015; 6CD011737
- Genetic variation in the ABCA1 gene, HDL cholesterol, and risk of ischemic heart disease in the general population.Atherosclerosis. 2010; 208: 305-316
- LCAT, HDL cholesterol and ischemic cardiovascular disease: a mendelian randomization study of HDL cholesterol in 54,500 individuals.J Clin Endocrinol Metab. 2012; 97: E248-E256
- Association of loss-of-function mutations in the abca1 gene with high-density lipoprotein cholesterol levels and risk of ischemic heart disease.JAMA. 2008; 299: 2524-2532
- Plasma HDL cholesterol and risk of myocardial infarction: a mendelian randomisation study.Lancet. 2012; 380: 572-580
- Effect of HDL-raising drugs on cardiovascular outcomes: a systematic review and meta-regression.PLoS One. 2014; 9e94585
- Effects of dalcetrapib in patients with a recent acute coronary syndrome.N Engl J Med. 2012; 367: 2089-2099
- Levels and changes of HDL cholesterol and apolipoprotein A-I in relation to risk of cardiovascular events among statin-treated patients: a meta-analysis.Circulation. 2013; 128: 1504-1512
- Triglyceride-mediated pathways and coronary disease: collaborative analysis of 101 studies.Lancet. 2010; 375: 1634-1639
- The effects of lowering LDL cholesterol with statin therapy in people at low risk of vascular disease: meta-analysis of individual data from 27 randomised trials.Lancet. 2012; 380: 581-590
- Glycemic load, glycemic index and risk of cardiovascular diseases: meta-analyses of prospective studies.Atherosclerosis. 2012; 223: 491-496
- Changes in lipoprotein (a), oxidized phospholipids, and LDL subclasses with a low-fat high-carbohydrate diet.J Lipid Res. 2010; 51: 3324-3330
- Effect of Trans-Fatty Acid Intake on Blood Lipids and LiPoproteins: A Systematic Review and Meta-Regression Analysis.World Health Organization, Geneva2016
- Trans fatty acids: are its cardiovascular risks fully appreciated?.Clin Ther. 2014; 36: 315-321
- Health effects of trans-fatty acids: experimental and observational evidence.Eur J Clin Nutr. 2009; 63: S5-S21
- Dietary cholesterol and cardiovascular disease: a systematic review and meta-analysis.Am J Clin Nutr. 2015; 102: 276-294
- Dietary cholesterol from eggs increases the ratio of total cholesterol to high-density lipoprotein cholesterol in humans: a meta-analysis.Am J Clin Nutr. 2001; 73: 885-891
- A prospective study of egg consumption and risk of cardiovascular disease in men and women.JAMA. 1999; 281: 1387-1394
- Egg consumption in relation to cardiovascular disease and mortality: the Physicians’ Health Study.Am J Clin Nutr. 2008; 87: 964-969
- Food intake patterns associated with incident type 2 diabetes: the Insulin Resistance Atherosclerosis Study.Diabetes Care. 2009; 32: 263-268
- Egg consumption and risk of type 2 diabetes in men and women.Diabetes Care. 2009; 32: 295-300
- Dietary fat and cholesterol and the risk of cardiovascular disease among women with type 2 diabetes.Am J Clin Nutr. 2004; 79: 999-1005
- The effect of a high-egg diet on cardiovascular risk factors in people with type 2 diabetes: the Diabetes and Egg DIABEGG study–a 3-mo randomized controlled trial.Am J Clin Nutr. 2015; 101: 705-713
- Dietary fish oil increases conversion of very low density lipoprotein apoprotein B to low density lipoprotein.Arteriosclerosis. 1989; 9: 58-66
- Omega-3 polyunsaturated fatty acids PUFA for type 2 diabetes mellitus.Cochrane Database Syst Rev. 2008; 1CD003205
- LDL-cholesterol-lowering effect of plant sterols and stanols across different dose ranges: a meta-analysis of randomised controlled studies.Br J Nutr. 2014; 112: 214-219
- Dietary sugars and cardiometabolic risk: systematic review and meta-analyses of randomized controlled trials of the effects on blood pressure and lipids.Am J Clin Nutr. 2014; 100: 65-79
- Low glycaemic index diets and blood lipids: a systematic review and meta-analysis of randomised controlled trials.Nutr Metab Cardiovasc Dis. 2013; 23: 1-10
- The effect of oat β-glucan on LDL-cholesterol, non-HDL-cholesterol and apoB for CVD risk reduction: a systematic review and meta-analysis of randomised-controlled trials.Br J Nutr. 2016; 116: 1369-1382
- A systematic review and meta-analysis of randomized controlled trials of the effect of konjac glucomannan, a viscous soluble fiber, on LDL cholesterol and the new lipid targets non-HDL cholesterol and apolipoprotein B.Am J Clin Nutr. 2017; 105: 1239-1247
- A systematic review and meta-analysis of randomized controlled trials of the effect of barley β-glucan on LDL-C, non-HDL-C and apoB for cardiovascular disease risk reduction.Eur J Clin Nutr. 2016; 70: 1239-1245
- Comparison of aerobic exercise, diet or both on lipids and lipoproteins in adults: a meta-analysis of randomized controlled trials.Clin Nutr. 2012; 31: 156-167
- Aerobic exercise and lipids and lipoproteins in women: a meta-analysis of randomized controlled trials.J Womens Health (Larchmt). 2004; 13: 1148-1164
- Exercise prevents the accumulation of triglyceride-rich lipoproteins and their remnants seen when changing to a high-carbohydrate diet.Arterioscler Thromb Vasc Biol. 2001; 21: 1520-1525
- Exercise prevents the augmentation of postprandial lipaemia attributable to a low-fat high-carbohydrate diet.Br J Nutr. 2001; 86: 197-205
- Effects of weight reduction on blood lipids and lipoproteins: a meta-analysis.Am J Clin Nutr. 1992; 56: 320-328
- Interventions that cause weight loss and the impact on cardiovascular risk factors: a systematic review and meta-analysis.Obes Rev. 2016; 17: 1001-1011
- Effects of low-carbohydrate vs low-fat diets on weight loss and cardiovascular risk factors: a meta-analysis of randomized controlled trials.Arch Intern Med. 2006; 166: 285-293
- Which amount of BMI-SDS reduction is necessary to improve cardiovascular risk factors in overweight children?.J Clin Endocrinol Metab. 2016; 101: 3171-3179
- Nibbling versus gorging: metabolic advantages of increased meal frequency.N Engl J Med. 1989; 321: 929-934
- High caloric intake at breakfast vs dinner differentially influences weight loss of overweight and obese women.Obesity (Silver Spring). 2013; 21: 2504-2512
- Beneficial effect of high energy intake at lunch rather than dinner on weight loss in healthy obese women in a weight-loss program: a randomized clinical trial.Am J Clin Nutr. 2016; 104: 982-989
Article info
Publication history
Published online: December 07, 2018
Accepted:
October 10,
2018
Received in revised form:
October 9,
2018
Received:
July 10,
2018
Identification
Copyright
© 2018 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.
