Are Garlic and Onion a Source of Flavour or Trans Fat?

What are Trans Fatty Acids?

According to the World Health Organization, TFAs are unsaturated forms of fatty acid which are processed from cooking, industrial or natural sources ^[2] 

Why are TFAs unsafe for consumption?

TFAs raise bad cholesterol levels while lowering good cholesterol levels, increasing the risk of heart disease and stroke. ^[3]

In addition to this, TFAs are also associated with the risk of possessing type 2 diabetes.  >2,78,000 mortalities occur every year worldwide due to the consumption of TFAs. ^[2] 

Why has the use of TFAs increased?

Trans fatty acids have several benefits, including remaining solid at room temperature, being readily available, and being cost-effective, which has led to their increased global use. ^[2]

Is it safe to use garlic and onion?

Garlic and onion contain anti-inflammatory, immunomodulatory, antioxidant and other useful properties however, cooking these at temperatures exceeding 140℃ leads to the development of trans fatty acids.^[1,4]

Are TFAs present in packaged foodstuff?

Packaged food such as potato chips, French fries, poori, etc. from the Indian market were also found to possess high amounts of TFAs in them due to subsequent frying cycles. ^[5]

Tips to reduce TFA intake:

1. Avoid overheating of sulphur containing items such as onion and garlic and cooking on low flame.

2. Always check the labels on the packaged food.

3. Use healthier oils in cooking that can withstand high temperatures such as olive oil, avocado oil, sesame oil, etc.

4. Consumption of TFA should be <2.2 grams per day for a 2,000 calorie diet.^[2]

What steps can be taken at national and international levels?

1. Implementation of strict rules for manufacturing and promotion of healthier oils. 

2. Introduction of public awareness programs with regard to cooking, avoiding overheating and repeated frying cycles. 

3. Compulsory limitation of 2 grams of industrially produced trans fat/100 grams of total fat in all food items. ^[2]

4. Increased testing of commercially available foods by laboratories. ^[2]

REFERENCES:

1. Obi, Junji, Taro Sakamoto, Kiyomi Furihata, Seizo Sato, and Masaki Honda. "Vegetables Containing Sulfur Compounds Promote Trans-Isomerization of Unsaturated Fatty Acids in Triacylglycerols During the Cooking Process." Food Research International 200 (2025): 115425. https://doi.org/10.1016/j.foodres.2024.115425.

2. World Health Organization. "Trans Fat." Who.int. Accessed January 8, 2025. https://www.who.int/news-room/fact-sheets/detail/trans-fat.

3. American Heart Association. "How Do Trans Fats Affect My Health?" Heart.org. Accessed January 8, 2025. https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/fats/trans-fat#:~:text=How%20do%20trans%20fats%20affect,of%20developing%20type%202%20diabetes.

4. Kumari, Neeraj, Manoj Kumar, Radha, José M. Lorenzo, Diksha Sharma, Sunil Puri, Ashok Pundir, et al. "Onion and Garlic Polysaccharides: A Review on Extraction, Characterization, Bioactivity, and Modifications." International Journal of Biological Macromolecules 219 (2022): 1047–1061. https://doi.org/10.1016/j.ijbiomac.2022.07.163.

5. Jain, A., S. J. Passi, and W. Selvamurthy. "Total Fat and Fatty Acid Profile Including TFA Content of Indian Fried Foods Versus the Oils Used for Frying." Journal of Food Science and Technology 61 (2024): 2185–2195. https://doi.org/10.1007/s13197-024-05989-z.

(Input from various sources)

(Rehash/Sanika Dongre/MSM)