Three stages of fat breakdown and a list of high-fat foods

Fat breakdown occurs in three stages: ① Fat mobilization: Triglycerides are broken down into glycerol and fatty acids by lipase. ② Glycerol oxidation: Glycerol is broken down into glycerol-3-phosphate by glycerol phosphokinase, and then loses two hydrogens to form dihydroxyacetone phosphate under the catalysis of glycerol phosphate dehydrogenase. It can then be converted into glucose and fatty acids, which bind to albumin and are transported to various tissues for β-oxidation. ③ Fatty acid β-oxidation: This catalyzes the activation of fatty acids to generate acyl-CoA, which helps metabolize intermediate products of fat, completing the process of fat metabolism in the body. Because fatty acid β-oxidation occurs in the mitochondria, acyl-CoA enters the mitochondria. This step requires carnitine transport. Acyl-CoA entry into the mitochondria is the main rate-limiting step in fatty acid β-oxidation. During starvation, when glycogen supply is insufficient, the activity of this enzyme increases, fatty acid oxidation increases, and the body relies on fatty acids for energy. This is why many women use dieting or even starvation to lose weight. Therefore, this method of weight loss can result in temporary weight loss, but once eating resumes, weight will increase sharply. ④ CH3Co~SCoA is completely oxidized, eventually turning into carbon dioxide (CO2) and water (H2O). The generated carbon dioxide is expelled from the body through respiration, while the water is expelled through perspiration and urination.

In conclusion, understanding the synthesis and metabolism of fats in the human body makes it clear that weight loss should be achieved through scientific and healthy methods. Scientific weight loss focuses on three key aspects: first, preventing the synthesis of excessive amounts of unwanted fats; second, accelerating the breakdown and metabolism of fats; and third, reducing fat storage in the body to maintain health and keep body fat percentage within a reasonable range.

**Ranking of Foods by Fat Content**

According to relevant statistics, the following ingredients, per 100 grams, contain relatively high levels of fat: chili oil (100g), sesame oil (100g), olive oil (99.9g), peanut oil (99.9g), soybean oil (99.9g), rapeseed oil (99.9g), wheat germ oil (99.9g), sesame oil (99.7g), salad oil (99.7g), lard (99.6g), butter (98g), cream (97g), ghee (94.4g), beef tallow (92g), pork caul fat (88.7g), pork fat (88.7g), pork belly fat (88.6g), pork fat (88.6g), mutton fat (88g), pine nuts (70.6g), pork ribs (59g), walnuts (58.8g), roasted pine nuts (58.5g), torreya nuts (57g), and egg yolk powder (55.1g). 53.4g sunflower seeds, 53g pistachios, 53g peanut butter, 52.9g roasted hazelnuts, 52.8g roasted sunflower seeds, 52.8g roasted pumpkin seeds, 52.7g sesame paste, 51g roasted almonds, 50.2g duck skin, 49.9g raw sunflower seeds, 48.8g raw cured pork, 48.4g potato chips, 48.3g Chinese sausage, 48.1g pumpkin seeds, 48g roasted peanuts, 47.1g fried peanuts, 46.1g black sesame seeds, 45.9g watermelon seeds, 45.4g almonds, 45.4g sweet almonds, 44.8g roasted watermelon seeds, 44.8g dried hazelnuts, 44.4g roasted peanuts, 44.3g raw peanuts, 41.3g Peking duck.