How Olive Oil Makes You Fat

Summary

This video explores the effects of different dietary fats on De Novo Lipogenesis (DNL) and how it influences the body’s fat composition. The experiment involved feeding participants diets with saturated fats (butter), polyunsaturated fats (safflower oil), and monounsaturated fats (canola oil). Findings show that diets rich in polyunsaturated and monounsaturated fats significantly increase DNL, leading to higher levels of saturated fats like palmitic and myristic acids in the body. The study suggests that while olive oil, with its polyphenols, may protect against DNL increases, polyunsaturated fats like safflower and canola oil promote fat accumulation.

Takeaways

• 😀 Diets rich in polyunsaturated fats, like safflower and canola oil, trigger **de novo lipogenesis (DNL)**, which increases the production of saturated fats like **palmitic acid** and **myristic acid**.
• 😀 Safflower oil, high in **linoleic acid**, increases **palmitic acid** production, despite a lower intake of this fat in the diet, indicating active DNL.
• 😀 **De novo lipogenesis** (DNL) is responsible for producing **palmitic acid** and **myristic acid** in the body, especially in response to polyunsaturated fats from oils like safflower and canola.
• 😀 Participants on a **safflower oil-based diet** showed a significant increase in **myristic acid** in their tissues, even though this fat is not present in safflower oil itself, suggesting it was synthesized via DNL.
• 😀 **Canola oil**, which activates key metabolic enzymes like **delta-6 desaturase (D6D)**, triggers a significant increase in both **palmitic acid** and **myristic acid**, showing that polyunsaturated fats can strongly promote DNL.
• 😀 The **canola oil diet** led to a nearly 20% increase in **palmitic acid** levels, confirming that polyunsaturated fats can have a pronounced effect on fat accumulation.
• 😀 In an experiment using **olive oil**, which contains monounsaturated fats and polyphenols, no significant increase in DNL was observed, suggesting that polyphenols might mitigate fattening effects.
• 😀 The **increase in palmitic acid** and **myristic acid** during the safflower and canola oil diets suggests that consuming large amounts of polyunsaturated fats may contribute to fat accumulation, even if these fats are not directly consumed.
• 😀 The **safflower oil** diet showed an increase in **palmitic acid** levels from 19.7% to 22.66% over 8 weeks, indicating a strong impact of polyunsaturated fat on fat metabolism.
• 😀 The **olive oil** diet experiment highlights the potential protective role of polyphenols in preventing DNL, but raises the question of how long these protective effects can last in the body.
• 😀 Overall, diets high in **polyunsaturated fats**, such as safflower and canola oil, can lead to fat storage and weight gain, as they significantly enhance **de novo lipogenesis**, even if the diet contains less saturated fat.

Q & A

What is the main focus of the study discussed in the video?

The main focus of the study is to explore how different types of dietary fats—particularly polyunsaturated fats (like safflower oil and canola oil)—affect de novo lipogenesis (DNL), a process where the body converts carbohydrates into fatty acids.

How did the baseline diet compare to the test diets in terms of fat composition?

The baseline diet was composed mostly of saturated fats, with 40% of calories from fat, 17% of which were from palmitic acid. In contrast, the test diets based on safflower oil and canola oil featured different fat compositions—safflower oil being high in polyunsaturated fats (PUFA) and canola oil being high in monounsaturated fats (MUFA), but also containing polyunsaturated fats.

What is de novo lipogenesis (DNL) and how is it measured in this study?

De novo lipogenesis (DNL) is the metabolic process where the body creates fatty acids from carbohydrates. In this study, DNL was measured by tracking the increase in specific fatty acids, like palmitic acid and myristic acid, in the phospholipids of participants, using isotope tracing to confirm whether these fatty acids were synthesized in the body.

How did the safflower oil-based diet affect palmitic acid levels?

On the safflower oil-based diet, palmitic acid levels increased despite the diet containing less palmitic acid compared to the baseline. This suggests that the body was synthesizing more palmitic acid via de novo lipogenesis.

What role does myristic acid play in the study and how did it change?

Myristic acid (a 14-carbon saturated fat) is another key indicator of de novo lipogenesis. The study showed that while myristic acid was almost absent in safflower oil, it increased significantly in participants’ phospholipids, indicating that it was synthesized through DNL during the safflower oil diet.

Why does the study focus on both palmitic acid and myristic acid?

Both palmitic acid and myristic acid are used as markers of de novo lipogenesis. The study specifically tracks changes in these fatty acids to determine whether the body is synthesizing them in response to dietary fat, and to compare the effects of different diets on this process.

What was the impact of the canola oil-based diet on DNL?

The canola oil-based diet caused a significant increase in both palmitic acid and myristic acid levels, suggesting that it strongly activates de novo lipogenesis. The study noted that the level of myristic acid nearly doubled over eight weeks.

What did the study involving olive oil reveal about DNL?

The olive oil study did not show an increase in de novo lipogenesis, possibly due to the high polyphenol content of olive oil, which may have protective effects. However, the video questions how long polyphenols can continue to protect against the fattening effects of monounsaturated fat.

What concern does the presenter raise regarding the long-term effects of consuming polyunsaturated fats?

The presenter raises the concern that while polyunsaturated fats, such as those found in safflower oil and canola oil, may initially have protective effects against fat accumulation, prolonged consumption might eventually lead to negative metabolic effects, particularly through the activation of de novo lipogenesis.

What conclusion does the presenter suggest about the impact of polyunsaturated oils on human metabolism?

The presenter suggests that diets rich in polyunsaturated oils, like safflower and canola oil, may lead to increased de novo lipogenesis and fat accumulation in the body, especially over the long term, despite their initial health benefits.