top of page

Chemistry of unsaturated fats

Monounsaturated fats are primarily found in plant-based products and some animal-based products. According to various studies, intake of unsaturated fats instead of trans and saturated fats have been shown to reduce the risk of heart diseases and type 2 diabetes. Scroll down to learn how the unsaturated fatty acid chemistry affects its nutritional qualities and about the difference between monounsaturated & polyunsaturated fats.

Sources of unsaturated fats 

IMG_4818.JPG
1 cup pecans:
Monounsaturated fats- 40 g
1 cup peanut butter:
Monounsaturated fats- 61 g
1 cup olive oil:
Monounsaturated fats- 158 g
100 gram cashew:
Monounsaturated fats- 24 g
1 cup avocado:
Monounsaturated fats- 15 g
100 gram salmon:
Monounsaturated fats- 1.5 g
1 cup safflower oil:
Monounsaturated fats- 164 g
The figure to the left includes foods high in monounsaturated fat. Hover over the figure to get their names and total count of monounsaturated fat.
These fats can be very beneficial in moderation
The figure to the right includes foods high in polyunsaturated fat. Hover over the figure to get their names and total count of polyunsaturated fat.
IMG_4801.JPG
1 cup sardines:
Polyunsaturated fats- 8 g
100 grams chia seeds:
Polyunsaturated fats- 24 g
1 cup walnuts:
Polyunsaturated fats- 38 g
1 cup sunflower seed:
Polyunsaturated fats-32 g
1 cup flaxseed:
Polyunsaturated fats- 48 g
1 cup corn oil:
Polyunsaturated fats-119 g
1 cup soybean oil:
Polyunsaturated fats-126 g
1 cup sardines:
Polyunsaturated fats- 8 g

Chemistry of unsaturated fats and how it affects the body

c7ra06088b-f1_hi-res_edited.jpg
Monounsaturated fat

Monounsaturated fat only has one double bond in its structure (mono indicates 1)

The chemical structures for monounsaturated and polyunsaturated fats are shown on the left. Their v-shape indicates that they are bent molecules, unlike the linear structure of the saturated fat molecule (see "Saturated Fats"). When a number of these molecules come together to create fat, their collective strength increases. Think "standing united makes you stronger." This attraction is called intermolecular force (IMF). When a bunch of monounsaturated or polyunsaturated molecules come together, their bent shape creates a larger distance between each of its own molecules. Since the molecules are unable to come so close together, the overall strength of the fat is weaker and the body has an easier time breaking it down than saturated or trans fats. When the body can't break down fat, it can end up lining artery walls, along with other materials (like cholesterol), and creating blood flow problems. This is called atherosclerosis.

This is why unsaturated fats are mostly found in liquid form, while saturated fats are found as solid at room temperature. The weak IMFs in an unsaturated fat keep molecules loosely attracted, whereas the IMFs in saturated fat are strong and keep it in a solid form. The different fats also have a large part to play in how the body handles cholesterol. To learn more about this, see "Cholesterol".

c7ra06088b-f1_hi-res_edited.jpg
polyunsaturated fat

Polyunsaturated fat has two or more double bonds in its structure (poly indicates multiple)

Furthermore, unsaturated fat has been shown to reduce the plaque on artery walls by decreasing the activation of monocytes next to artery walls. They are white blood cells that are important to the immune system, but unfortunately, contribute to atherosclerosis. Monocytes work through phagocytosis, which is the uptake or "eating up" of foreign substances that can threaten the body. Unfortunately, it does the same when it encounters these fatty deposits, but ends up just accumulating in them and making it a bigger deposit. 

​

Some studies have shown that polyunsaturated fat can be even more beneficial than monounsaturated fat. While both types of fats can potentially help patients to lose weight and decrease blood pressure & triglyceride levels, it has been observed that the effects of polyunsaturated fat are more prominent than monounsaturated. However, it is important to include a combination of monounsaturated and polyunsaturated fats into the diet. 

The animation to the left portrays the effects of the build up of fat on arteries, blood vessels that carry blood throughout the body. Healthy arteries are flexible, a quality necessary for adequate blood flow. Arteries with plaque lose their elasticity. The build up of plaque will start off by restricting blood flow by narrowing the passageway for the blood. As the build up continues, blood flow will get more restricted. This blockage can cause a blood clot, completely cutting off blood flow. The lack of blood flow to the brain causes stroke. Lack of blood flow to the heart causes heart attacks. Overall, this would increase risk of cardiovascular disease and peripheral artery disease, in which blood flow to limbs is limited. 

​

Conclusion: consumption of unsaturated fats instead of saturated and trans fats decreases risk of cardiovascular issues.  

bottom of page