Academics at Jiangnan University in China sought study to analyse the effects of dietary n-3 and n-6 PUFAs on the distribution of different types of fatty acids and their bioavailability along the gut.
To do so, mice were fed with experimental control, n-3 and n-6 PUFA diets for seven days and were then euthanised
The guts were taken and each was divided into 17 segments for fatty acid analysis.
They found that supplementing n-3 fatty acids significantly changed the ratio of n-6/n-3 PUFAs, increased the bioavailability of n-3 PUFAs, and altered fatty acid distribution.
“Through the progress of fatty acid absorption, the percentage of monounsatrurated fatty acids along the gut became higher, while the SFA levels were steady, except in the last two segments,” they wrote in the journal Lipids and Health Disease.
“This phenomenon was particularly obvious when mice were fed with the high n-3 diet. This data suggests that PUFAs could slow or prevent the absorption of SFAs, and n-3 PUFAs have a stronger effect than n-6 PUFAs.”
They added their results showed that n-3 and n-6 PUFA composition in mice blood responded efficiently to experimental diets as early as three hours after feeding.
“These findings lead us to hypothesize that n-3 PUFAs can inhibit the absorption of saturated fatty acids in the mouse gut, through a mechanism that remains to be identified.”
“To our knowledge, this is the first report of this phenomenon,” they stated.
Meanwhile gut fatty acid analysis revealed that an n-3 PUFA-rich diet can decrease the ratio of n-6/n-3 PUFAs along the gut and increase the bioavailability of n-3 PUFAs in the whole gut.
This is beneficial because high ratios of n-6/n-3 PUFAs, along with high fat consumption in the Western diet, have been associated with increased incidences of obesity, diabetes, cardiovascular disease and cancer, noted the researchers.
“Nutritionists often advise their patients to lower the n-6/n-3 fatty acid ratio in their diet,” they wrote.
The study concluded: “The results indicated that supplements of n-3 fatty acids can increase the bioavailability of n-3 PUFAs, thus changed the ratio of n-6/n-3 PUFAs and altered fatty acid distribution.
“Besides, in the n-3 diet group, the absorption of saturated fatty acids (SFAs) along the gut was found to be inhibited.”
Source: Lipids in Health and Disease
“Dietary intake of n-3 PUFAs modifies the absorption, distribution and bioavailability of fatty acids in the mouse gastrointestinal tract”
Authors: Zhennan Gu, et al.
The Chinese version of this story can be found here.