Lard is one of the most pampered greases in Chinese kitchens.
The snow-white color and oily texture seem ordinary, but it can make the food instantly fragrant.
Many families have the habit of eating lard, put a spoonful of lard when stir-frying, even if it is boring and tasteless greens, it will be upgraded in an instant and become a fragrant dish.
A bowl of simple white rice, mixed with lard, is even more fragrant, and it is the taste of home in the memory of countless people.
Many people have difficulty resisting the temptation of lard!
So the question is, what happened to the health of those who have eaten lard for a long time?
The reason why we find lard delicious is mainly due to the "Maillard reaction".
At high temperatures, the carbonyl compounds in lard undergo complex reactions with amino compounds such as proteins/amino acids, producing hundreds of different odor molecules, including reduced ketones, aldehydes, and heterocyclic compounds[1].
In addition, nitrogenous sulfur-containing compounds and pyrazine-like substances that may be produced in the boiling of lard [2] allow lard to have a delicious flavor and achieve great satisfaction of smell and taste.
(Source: soogif)
However, the aroma of lard from different boiling methods and from different parts is also different, such as pork with back oil, which has a stronger aroma and a heavier burnt taste of plate oil and mesh oil.[3]
Due to the baptism of high temperatures, these odor molecules are not too easy to volatilize, and will always be low-key in food, and can only be smelled by us when the temperature is very high.
This explains why stir-frying dishes in lard are so fragrant, turning bland ingredients into earthly delicacies that exude a seductive aroma.
(Source: soogif)
100 g of lard contains 95 mg of cholesterol, 0.6 mg of vitamin E, 2.5 mcg of vitamin D, 0.11 mg of zinc, and 0.2 mcg of selenium[4].
In addition, lard is almost always fat, especially - saturated fat is more worthy of attention.
Fats are divided into two types: "saturated fats" and "unsaturated fats". Saturated fat is generally believed to be relatively unhealthy and is widely associated with obesity and cardiovascular disease.
Of the 100 grams of lard oil, saturated fat also accounts for about 39.2 grams, although it accounts for more than half of the saturated fat.
Compared with another common type of edible oil, vegetable oil, lard contains 2.58 times the saturated fat of soybean oil, 2.92 times that of olive oil, and 2.25 times that of peanut oil [5,6,7], although lard is not the highest saturated fat content in animal oil, but it is a well-deserved "saturated fat king" in the oil that is often eaten.
Of course, this is also why lard is easy to solidify at room temperature, while vegetable oil is mostly liquid - the higher the saturated fat content, the more "hard" the fat.
So, what changes will occur in the body after eating lard for a long time?
This has to be said by experimental research.
Scholars have done a lot of animal experiments to explore the health effects of lard.
For example, a Canadian scholar fed rats a high-fat diet based on lard and vegetable oil, and after 14 weeks found that compared with the mice in the normal fat diet group, the weight of the lard group and the vegetable oil group increased, but the weight and subcutaneous fat of the piglets in the lard group were 30% higher than those in the vegetable oil group [8].
A study by Huazhong University of Science and Technology found that long-term consumption of lard or vegetable oil can cause obesity-related inflammation and insulin resistance in rats, and reducing lard in the diet or replacing lard with vegetable oil can weaken this change [9].
——A study in Shandong found that long-term consumption of lard can lead to thyroid hypertrophy and hypothyroidism in mice. Stop eating lard for a short time, and these damages cannot be recovered [10].
A korean study has found that long-term consumption of lard stimulates the development of prostate cancer in rats and reduces survival rates, possibly because soluble factors derived from adipose tissue can promote the growth and metastasis of prostate cancer through mechanisms such as paracrine and endocrine [11].
These animal experiments all point to the same problem - long-term consumption of lard has had a considerable negative impact on animal health.
However, after all, these are only animal experiments, and cannot be directly inferred from people.
The health hazards of lard may be mainly related to saturated fat, and long-term intake of too much saturated fat will increase the risk of diabetes, hypertension, hyperglycemia and other diseases and stroke in many ways [12].
However, there is no need to "talk about lard discoloration", control intake, you can enjoy safety and deliciousness at the same time.
(Source: soogif)
How much lard to eat every day, is it not too much?
Unfortunately, there are currently no clear measurement rules.
However, we can roughly judge based on the recommended amount of fat per day.
According to the Scientific Research Report on Dietary Guidelines for Chinese Residents (2021), it is recommended that the daily intake of cooking oil should not exceed 30 grams[13]; the Dietary Guidelines for Chinese Residents 2016 recommends that adults should not consume more than 25 to 30 grams of cooking oil per day.
In the 2020 "oil reduction publicity" of the Disease Control Bureau of the National Health Commission, it was advocated that stricter, recommending that healthy adults should not consume more than 25 grams of cooking oil per day [14].
So overall, for healthy adults, it is best (excellent) for cooking oil to consume no more than 25 grams per day (excellent), at least no more than 30 grams (passing line, ).
(Source: soogif)
Of course, in addition to the "quantity" of cooking oil intake, "quality" is also very critical
According to the Chinese residents' dietary nutrient reference intake DRIs, the daily intake of saturated fatty acids should not exceed 10% of total energy, taking young and physically active women as an example, it is probably no more than 20 grams.
The "saturated fatty acid intake" here should be viewed as a whole, and other foods we eat every day such as milk, meat, eggs, nuts, and soybeans also contain some saturated fatty acids, so the share that can really be left for lard may be pitiful.
(Source: soogif)
In addition to controlling lard intake, it is also necessary to pay attention to the intake of red meat such as pork and various foods made with lard, such as rose cakes, lard dumplings, eight treasure rice, green dough, lotus puff pastry, butter cakes, etc.
Back to the issue of eating oil, the healthiest way is actually - it is best to replace lard with vegetable oil rich in unsaturated fatty acids!
Special Author: Zhang Sifan
Master of Basic Medicine at Imperial College London
Reviewer: Li Yuanyuan
Registered Dietitian
bibliography
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ZOU Jiankai. Analysis by gas chromatography/mass spectrometry of volatile oil components of lard[J].,Analytical Chemistry,2002.]
Pan Kailin. Comparison of the quality characteristics of lard in different parts[J].Food Science and Technology, 2016
[4]https://fdc.nal.usda.gov/fdc-app.html#/food-details/171401/nutrients
[5]https://fdc.nal.usda.gov/fdc-app.html#/food-details/171411/nutrients
[6]https://fdc.nal.usda.gov/fdc-app.html#/food-details/171413/nutrients
[7]https://fdc.nal.usda.gov/fdc-app.html#/food-details/690476/nutrients
[8] Kubant R, Poon AN, Sánchez-Hernández D, et al. A comparison of effects of lard and hydrogenated vegetable shortening on the development of high-fat diet-induced obesity in rats. Nutr Diabetes. 2015;5(12):e188. Published 2015 Dec 14. doi:10.1038/nutd.2015.40
[9] Wang X, Cheng M, Zhao M, et al. 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. Eur J Nutr. 2013;52(3):1181-1189. doi:10.1007/s00394-012-0428-z
[10] Shao SS, Zhao YF, Song YF, et al. Dietary high-fat lard intake induces thyroid dysfunction and abnormal morphology in rats. Acta Pharmacol Sin. 2014;35(11):1411-1420. doi:10.1038/aps.2014.82
[11] Cho HJ, Kwon GT, Park H, et al. A high-fat diet containing lard accelerates prostate cancer progression and reduces survival rate in mice: possible contribution of adipose tissue-derived cytokines. Nutrients. 2015;7(4):2539-2561. Published 2015 Apr 9. doi:10.3390/nu7042539[12]Oparin, M.L., Mamaev, A.B. & Oparina, O.S. The Density of Larks (Alaudidae, Aves) in the Semi-Desert of the Trans-Volga Region in Connection with Landscape Wetting Dynamics. Biol Bull Russ Acad Sci 47, 1385–1391 (2020). https://doi.org/10.1134/S1062359020100167
[12] Saturated Fat. American Heart Association.https://www.heart.org/en/
[13] Scientific Research Report on Dietary Guidelines for Chinese Residents (2021)
National Health Commission of the People's Republic of China.
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