scholarly journals Optimal macronutrient balance

1999 ◽  
Vol 58 (2) ◽  
pp. 421-425 ◽  
Author(s):  
Michael J. Gibney

There is at present a justifiable debate as to the optimum level of total dietary fat which will reduce the risk of obesity without an elevation of plasma triacylglycerol or a depression of plasma HDL-cholesterol. Total plasma cholesterol and LDL-cholesterol levels are lowered and risk of fatal myocardial infarction is lowered when either saturated or trans-unsaturated fatty acids are replaced isoenergetically by either monounsaturated or polyunsaturated fatty acids. The triacylglycerol-raising and HDL-lowering effects of low-fat high-carbohydrate diets can be over-come with low intakes of n−3 polyunsaturated fatty acids and moderate exercise. Whilst a reduction in dietary fat is being attained in many countries, the reduction is uniform across all fatty acids, leaving dietary fat composition unchanged. The ability of low-fat diets to reduce cholesterol and cause a fall in body weight is not influenced by the carbohydrate ratio starch: sugars in the diet. However, weight-gain susceptibility to high intakes of dietary fat and the plasma cholesterol responsiveness to diet are considerably influenced by common genetic polymorphisms.

1993 ◽  
Vol 17 ◽  
pp. 57-61 ◽  
Author(s):  
M. J. Gibney

AbstractEarly research in man at the end of the fifties and beginning of the sixties indicated that the composition of dietary fat influenced plasma cholesterol levels. In effect this research showed that plasma cholesterol was raised by saturated fatty acids (SFA), was lowered by polyunsaturated fatty acids (PUFA) and was not influenced by monounsaturated fatty acids (MUFA). Within the SFA it was also observed that the greater the chain length, the lesser the cholesterol raising effect. A quantitative relationship between the change in blood cholesterol (ΔC) resultant from changes in the percentage energy from SFA (ΔS) and PUFA (ΔP) was established as ΔC = 1.3 (2ΔS − ΔP). For the ensuing tivo decades this association dominated nutrition education programmes with the message that ‘saturates or animal fats raise blood cholesterol and polyunsaturates or vegetable oils lower blood cholesterol’.In the 1980s it became evident that the two main fractions of blood cholesterol yielded different risks for coronary heart disease. Low-density lipoprotein (LDL) cholesterol raised the risk and high-density lipoprotein (HDL) cholesterol lowered the risk. Earlier work on the qualitative effect of dietary fat was now repeated to examine the direction of change of the LDL and HDL subfractions of plasma cholesterol. Broadly speaking these data showed that SFA raised LDL cholesterol and had little effect on HDL cholesterol. PUFA lowered LDL cholesterol but when the intake was high, also lowered HDL cholesterol. Whilst this summarizes events leading up to current thinking on dietary fats and blood cholesterol, it is likely in the near future to be linked to another area of research involving the antioxidant vitamins and pro-vitamins (vitamin E, vitamin C and β-carotene). A growing body of data in the literature indicates a protective effect of antioxidant vitamins in epidemiological trials.Notwithstanding these findings, it is likely that dietary advice will continue to seek a lowering of SFA intake. PUFA intake will be capped and MUFA intake will be a more acceptable alternative. However, with increasing emphasis on antioxidant vitamin status, such advice is likely to be coupled with advice on increased consumption of fruit and vegetables.


1998 ◽  
Vol 79 (1) ◽  
pp. 23-30 ◽  
Author(s):  
Anita S. Wells ◽  
Nicholas W. Read ◽  
Jonathan D. E. Laugharne ◽  
N. S. Ahluwalia

The effects on mood of reducing dietary fat while keeping the energy constant were examined in ten male and ten female healthy volunteers aged between 20 and 37 years. Each volunteer consumed a diet containing 41% energy as fat for 1 month. For the second month half of the subjects changed to a low-fat diet (25% energy from fat) and the remainder continued to eat the diet containing 41% energy from fat. Changes in mood and blood lipid concentrations were assessed before, during and at the end of the study. Profile of mood states (POMS) ratings of anger–hostility significantly increased in the intervention group after 1 month on the low-fat diet, while during the same period there was a slight decline in anger–hostility in the control subjects (group F 6.72; df 1,14; P = 0.021). Tension–anxiety ratings declined in the control group consuming the higher fat diet but did not change in the group consuming the low-fat diet (group F 6.34; df 1,14; P = 0.025). There was a decline in fasting concentrations of HDL-cholesterol after the low-fat diet and a small increase in subjects consuming the medium-fat diet (group F 4.96; df 1,12; P = 0.046), but no significant changes in concentrations of total serum cholesterol, LDL-cholesterol or triacylglycerol were observed. The results suggest that a change in dietary fat content from 41 to 25% energy may have adverse effects on mood. The alterations in mood appear to be unrelated to changes in fasting plasma cholesterol concentrations.


1989 ◽  
Vol 62 (02) ◽  
pp. 797-801 ◽  
Author(s):  
E Berg Schmidt ◽  
E Ernst ◽  
K Varming ◽  
J O Pedersen ◽  
J Dyerberg

SummaryPlasma lipids and haemostasis were investigated in 17 patients with hyperlipidaemia before and after 6 weeks supplementation with 6 g n-3 fatty acids. Nine of the patients had type IIa and 8 had type IV hyperlipidaemia. No effect on plasma cholesterol, LDL- or HDL-cholesterol were seen, but plasma triglycerides decreased after n-3 supplementation. Apolipoprotein B increased and apolipoprotein A1 decreased after the oil supplement. The bleeding time was prolonged, but platelet aggregation was unaltered by n-3 fatty acids. Protein C activity increased in type II a and decreased in type IV after the supplement. Fibrinolysis was markedly depressed while von Willebrand factor antigen was reduced after intake of n-3 fatty acids.


2009 ◽  
Vol 2009 ◽  
pp. 212-212
Author(s):  
S J Hosseini Vashan ◽  
N Afzali ◽  
A Golian ◽  
M Malekaneh ◽  
A Allahressani

Palm oil is the most abundant of all oils produced globally. It is very high in saturated fatty acids specifically palmitic acid, but other fatty acids (monounsaturated (MUFA) and polyunsaturated) are presented at low concentrations. In the processing plant some high amount of oleic acid with some other unsaturated fatty acids are extracted and marketed as Palm olein oil, and used to reduce blood or egg cholesterol (Rievelles et al., 1994). The objective of this study was to determine the optimum level of dietary palm olein oil required to enrich the mono-unsaturated fatty acid content of yolk, egg cholesterol and antibody titre.


1986 ◽  
Vol 6 (8) ◽  
pp. 931-955 ◽  
Author(s):  
Olukemi Olubajo ◽  
Mary W. Marshall ◽  
Joseph T. Judd ◽  
James T. Adkins

2021 ◽  
Vol 14 (1) ◽  
pp. 11-22
Author(s):  
Prasetyo Nugroho ◽  
Komang Gede Wiryawan ◽  
Dewi Apri Astuti ◽  
Wasmen Manalu

Background and Aim: Flushing with the manipulation of fatty acids, particularly polyunsaturated fatty acids, like linoleic and α-linolenic acids in the ration, is a strategy to raise the nutritional status of the female mammals to improve ovarian function and follicle development. This study was designed to investigate the effectiveness of flushing supplementation with different types of polyunsaturated and saturated fatty acids in stimulating follicle growth and development during estrus in Ettawa Grade does with a low initial body condition score (BCS ≤2). Materials and Methods: Eighteen Ettawa Grade does in the second parity, with an average body weight of 32.11±2.19 kg, were divided into three groups according to the fatty acid supplemented to their ration: (i) About 2.8% lauric acid flushing (group); (ii) 2.8% linoleic acid flushing (LA group); and (iii) 2.8% a-linolenic acid flushing (ALA group). The ration was formulated to be isocaloric (total digestible nutrient = 77%) and isonitrogenous (crude protein = 15%). The experiment was conducted for 35 days; that is, 14 days for acclimatization and synchronization of the estrous cycle and 21 days for fatty acid flushing until the appearance of the next estrus. A completely randomized design was applied. Results: According to the results, none of the different fatty acids in the ration affected the nutrient intakes, BCSs, average daily gains, and plasma glucose, cholesterol, and progesterone concentrations of the three groups of does. However, the BCSs (by 0.8-0.9) and the plasma cholesterol concentrations were higher after fatty acid flushing for 21 days than before the flushing period. The ALA group had the highest number of large-sized preovulatory follicles, whereas the LAURIC group had the highest plasma estradiol concentration during estrus. All three groups had similar plasma progesterone concentrations during estrus after fatty acid flushing. Conclusion: Flushing supplementation with 2.8% ALA from flaxseed oil gave the best results in terms of stimulating the highest number of large-sized preovulatory follicles in Ettawa Grade does.


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