Studies: Plant-based Low Carb Diet Aids Weight Loss, Cholesterol
University researchers have found that a low-carb plant-based diet helps lose weight and reduce bad cholesterol, including LDL-c and triglycerides.
The research was led by David J.A. Jenkins, MD, PhD, DSc, Professor of Nutrition at the University of Toronto.
The researchers tested two diets that have been found to reduce LDL-c, triglycerides and produce weight loss. In their introduction and analysis of previous research, the researchers wrote in the British Medical Journal, Lancet (the statements below were referenced to a list of 32 clinical research findings – see references below*):
“Many popular weight loss diets emphasize carbohydrate restriction (Atkins, Eddies, South Beach, Zone). However, a high content of animal products, rich in saturated fat and cholesterol, may make conventional low-carbohydrate diets less appropriate for those with hypercholesterolaemia. Even during active weight loss, these high-saturated fat diets do not lower serum low-density lipoprotein cholesterol (LDL-C) below baseline and there is concern that if such diets continue to be eaten when weight loss has ceased, a more atherogenic blood lipid profile may result. These concerns have prompted exploration of other weight loss strategies, but only modest reductions in LDL-C have been observed.
“By contrast vegan diets significantly lower LDL-C. Trials of vegan and vegetarian diets also reduce progression of coronary heart disease and improve diabetes control. Plant food components such as vegetable proteins, vegetable oils, nuts and viscous fibers, reduce serum lipids in many studies and may increase flow-mediated vasodilatation. Nuts, fiber and vegetarian diets in general, all reduce coronary heart disease and diabetes in cohort studies. Finally, in cohort studies, low-carbohydrate diets, high in vegetable oils and proteins as opposed to animal products, reduce coronary heard disease events and diabetes incidence in women, while lower red meat intake reduces total, cardiovascular and cancer mortality. Most recently a large randomized controlled trial confirmed the effect of nuts and increased vegetable oil (olive oil) intake in reducing cardiovascular events in the context of a Mediterranean diet.”
Moving forward from these previous research findings, the researchers conducted a clinical study that tested two diets: A lacto-ovo vegetarian diet and a low-carb plant-based diet, with its protein coming from foods like nuts, gluten-containing grains and soy. The choices of higher-protein foods was “self-selected” by the participants – meaning they ate selected foods they preferred to eat.
In all, 23 human adults who were overweight with metabolic disease symptoms (lack of glucose control) completed the six month study. At the beginning and the end of the study, weight, LDL-c, triglycerides, total cholesterol and apolipoprotein B:A1 ratios were measured among the subjects.
After the six months, the plant-based low-carb group lost an average of 7 kilograms each – equivalent to over 15 pounds – and those on the lacto-ovo diet lost an average of nearly 13 pounds each.
And both groups also had significantly lower LDL and triglyceride levels. The plant-based low-carb diet resulted in an average reduction of 27 mg/dL in LDL-c levels, and the lacto-ovo diet resulted in an average reduction of almost 11 mg/dL in LDL-c – still a significant result.
Meanwhile, the plant-based low-carb diet participants saw their average triglyceride levels go down by over 50 mg/dL while the lacto-ovo group’s triglycerides went down by almost 10 mg/dL.
Both of these factors – LDL-c and triglycerides – are significantly linked with heart disease.
Furthermore, levels of Apo B/A1 – also linked to heart disease – went down significantly, dropping by 0.57 in the plant-based low-carb diet and 0.05 in the lacto-ovo diet.
The researchers concluded that the plant-based low-carb diet…:
“containing increased protein and fat from gluten and soy products, nuts and vegetable oils, had lipid lowering advantages over a high-carbohydrate, low-fat weight loss diet, thus improving heart disease risk factors.”
Other research has found that a low-carb diet with greenfoods can significantly improve weight loss efforts.
Jenkins DJ, Wong JM, Kendall CW, Esfahani A, Ng VW, Leong TC, Faulkner DA, Vidgen E, Paul G, Mukherjea R, Krul ES, Singer W. Effect of a 6-month vegan low-carbohydrate (‘Eco-Atkins’) diet on cardiovascular risk factors and body weight in hyperlipidaemic adults: a randomised controlled trial. BMJ Open. 2014 Feb 5;4(2):e003505. doi: 10.1136/bmjopen-2013-003505. http://bmjopen.bmj.com/content/4/2/e003505.full
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