Lard as a fat source in the diet

According to the raport of World Health Organization, number of overweight people in the World (BMI > 25 kg/m²) in 2002 came to 1 billion.300 hundred millions of them are obese (BMI >30 kg/m²). Increase of obesity through the Word is seeing for a number of years, and, in 2008 it was accounted, that 2.3 billion are overweight, and, respectively, 700 millions are obese. Why does governmental recommendations doesn't work? And why they don't want to admit that? We are living in fat hypothesis - what says, that heart diseases and obese is a result of fat consumption. But, science don't support well that view. Here, I'll write a litle bit about lard. Enjoy.

Dietary fat
Dietary fat could be distributed with regard of number of unsaturated bonds in a carb chain. In this way, we have saturated fatty acids - SFA (0 unsaturated bond), monounsaturated fatty acids - MUFA (1 unsaturated bond) and polyunsaturated fatty acids - PUFA (more than 1 unsaturated bond). Depending on first unsaturated bond in carb chain in PUFA from methyl group, we divide those fatty acids as n-3, n-6, n-9 family. Each of them has another properties at human body.

PUFA n-3 and n-6 family belong to the essential fatty acids - EFA, because we can not synthesize them de novo, and, they are essential for proper system metabolism. They have proven significence role in work of every human body cell [Simopoulos 1999, Wcisło and Rogowski 2006, Dobryniewski et al. 2007], especially n-3 fatty acids, particularly at circulatory system [Wang et al. 2006], and systemic inflammation [Calder 2006, Nowak 2010]. Linoleic acid (18:2) is a representative of n-6 fatty acids family, while alpha-Linolenic (18:3) acid represents n-3 fatty acids family. The number in round backet, respectively, tells about the number of carb atoms in carb chain and number of unsaturated bounds. In human nutrition, it is important to keep equilibrium between n-6/n-3 fatty acids. The ratio should come to 1:4-6.

MUFA, which represents oleic acid (18:1), is found mainly in olive oil. With phenols compound, they have wide positive impact at human body, mainly at lipid profile [Cicerale et al. 2010]. This fatty acids constitute a big part of energy source in Mediterranean diet.

In view of SFA, we should mention mainly lauric (12:0), myristic (14:0), palmitic (16:0) and stearic acid (18:0). Myristic and palmitic acids are those, which increase blood total cholesterol level - TC. Lauric acid decrease the proportion of TC/HDL-C (High density lipoprotein cholesterol), and stearic acid decrease the blood-cholesterol level of LDL-C (low density lipoprotein cholesterol). So, not every SFA has same properties. How is it with lard? Does it safe or not?

Lard nutrients
Accordin to the data found on USDA web (NDL/FNIC Food Composition Database Home Page, National Nutrient Database for Standard Reference) we find out, that 100g of lard contain 100g of fat, providing 902 kcal energy. It is almost free of mineral compounds. In view of vitamins, we can specify choline (49.7 mg), vitamin E (0.6 mg) and vitamins D (2.5 ug, 102 IU). Lard include only 95 mg of cholesterol. Fatty acids composition is presented below (tab. 1).

Tab. 1. Fatty acids composition of lard [g/100g]. The main composition of fatty acids is making up by MUFA (45 %), representing almost in 100% by oleic acid (18:1) - with positive properties for your circulatory system, for you blood lipid profile. Next to them are SFA (30 %), constituted mainly by unhealthy palmitic acid (24 %) and decreasing LDL-C stearic acid (13.5 %). The lowest part has PUFA (11.2 %), in which n-6:n-3 proportion amount to 10:1.

Fatty acids
SFA		MUFA		PUFA
Fatty acid	Content [g]	Fatty acid	Content [g]	Fatty acid	Content [g]
Total	39.2	Total	45.1	Total	11.2
10:0	0.1	16:1	2.7	18:2	10.2
12:0	0.2	18:1	41.2	18:3	1.0
14:0	1.3	20:1	1.0
16:0	23.8
18:0	13.5

Discussion
As we can see, more than half of fatty acids in lard are healthy and has positive impact on lipid profile. What would happen, if we exchange carbohydrates with fat in diet, including SFA? Micha and Mozaffarian (2010) meta-analysis [Micha and Mozaffarian 2010] provide us interesting results. Accordingly to the SFA, they increased TC, LDL-C, HDL-C and decreased triglycerides - TG. Monounsaturated and polyunsaturated fatty acids decreased TG and LDL-C. Unhealthy influence of SFA was seen only, when they were compare with PUFA.

On the basis of above-mentioned data, we can conclude, that there is no basis for elimination lard from diet or reduction of SFA intake to the recommended level <10% [Micha and Mozaffarian 2010, Cordain 2012]. The higher intake of fat in diet is not correlated with incidence of cardiovascular diseases [Oh et al. 2005 and Cordain 2012]. It is important to mention, that fatty acid composition from meat, meat products, milk and milk products depends of the animal food composition. So, the fatty acids composition of lard, is also changeable, especially content of n-6 and n-3 fatty acids family may change considerably.

In one research carried out on obese rats, group with high fat diet (lard or soybean oil) secreted much more proinflammatory cytokines and osteopontin than group with standard diet. Osteopontin expression were reduced only in rats group, which diet were reduced on fat (from lard). Basicly on that results, researchers concluded, that reduction of lard consumption or izocaloric exchange for soybean oil may decrease systemic inflammation caused by obesity or insulin resistance [Want et al. 2012]. Osteopontin has participation with formation of kidney stones, development of carcinogenesis, autoimmune diseases, regulation of inflammation processess (working both, pro- and antiinflammatory) and atherosclerosis [Witkwiewicz et al. 2010]. We don't know much about osteopontin yet, and future data are needed [Wang et al. 2012]. It's worth mention, that soybean oil is not as healthy, as some researches claim [Cordain 2012]. Lard, seems to be a healthy part of the human diet.

Literature

1.       Calder PC. n-3 Polyunsaturated fatty acids, inflammation, and inflammatory diseases. Am J Clin Nutr. June 2006. vol. 83 no. 6. S1505-1519S.

2.       Cicerale S., Lucas L., Keast R. Biological Activities of Phenolic Compounds Prezent in Virgin Olive Oil. Int. J. Mol. Sci. 2010, 11, 458-479.

3.       Cordain L. The paleo answer. 2012. John Wiley & Sons, Inc., Hoboken, New Jersey. ISBN 978-1-118-16011-4.

4.       Dobryniewski J, Szajda SD, Waszkiewicz N, Zwierz K. Biologia niezbędnych nienasyconych kwasów tłuszczowych (NNKT). Przegląd Lekarski 2007 / 64 / 2. 91-99.

5.       Micha R, Mozaffarian D. Saturated Fat and Carfdiometabolic Risk Factors, Coronary Heart Disease, Stroke, and Diabetes: a Fresh Look at the Evidence. Lipids. 2010 October; 45(10): 893-905.

6.       Nowak J.Z. Przeciwzapalne „prowygaszeniowe” pochodne wielonienasyconych kwasów tłuszczowych omega 3 i omega 6. Postepy Hig Med. Dosw. (online), 2010; 64: 115-132.

7.       Oh K., Hu FB., Manson JE., Stampfer MJ., Willet WC. 2005. Dietary Fat Intake and Risk of Coronary Heart Disease in Women: 20 Years of Follow-up of the Nurses’ Health Study. Am. J. Epidemiol. (2005) 161 (7): 672-679.

8.       Simopoulos A.P. Essentials fatty acids in health and chronic disease. Am J Clin Nutr September 1999 vol. 70 no. 3. 560s-569s.

9.       Wang C., Harris W.S., Chung M., Lichtenstein A.H., Balk E.M., Kupelnick B., Jordan H.S., Lau J. n-3 Fatty acids from fish or fish-oil supplements, but not alfa-linolenic acid, benefit cardiovascular disease outcomes in primary- and secondary-prevention studies: a systematic review. Am J Clin Nutr. July 2006. vol. 84. no. 1. 5-17.

10.   Wang, X., Cheng, M., Zhao, M., Ge, A., Guo, F., Zhang, M., Yang, Y., Liu, L., Yang, N. Differential effects of high-fat-diet rich in lard oil or soybean oil on osteopontin expression and inflammation of adipose tissue in diet-induced obese rats. European Journal of Nutrition 2012, Pages 1-9.

11.   Wcisło T., Rogowski W. Rola wielonienasyconych omega-3 w organizmie człowieka. Cardiovascular Forum 2006, 11, 3, xx-xx. Copyright 2006 Via Medica, ISSN 1425-3674.

12.   Witkiewicz W., Czyżewska-Buczyńska A., Bałasz S., Gnus J.J. Rola osteopontyny w chorobach sercowo-naczyniowych. Pol. Merk. Lek. 2010, XXIX, 170, 79.