The Effect of Chia Seeds on High-Density Lipoprotein (HDL) Cholesterol

Chia seeds are touted as a healthy food capable of providing a beneficial effect on high-density lipoprotein (HDL) cholesterol. Similar claims have been made for oats in various forms, claiming that they improve cholesterol or are in some way "heart healthy."

This study aims to demonstrate the effect of daily consumption of chia seeds, if any, on HDL cholesterol levels and compare this to the effects of oats on HDL levels.

This pilot study is a randomized controlled trial performed at an academic primary care center. Participation was voluntary, and all participants provided written consent prior to enrollment. There were no exclusion criteria other than that participants must be adults and willing to come in to get their cholesterol profiles checked at the beginning and end of the study. The participants consumed their assigned breakfast in a standard serving size for a month with blood draws and weights recorded before and after the diet. The patients' cholesterol profiles were also compared with their weights. To standardize the delivery of chia seeds, the group consuming chia seeds mixed them with oatmeal. The three meal groups consisted of Cheerios (red group), oatmeal (white group), and oatmeal with chia seeds (blue group). Initially, there were a total of 11 subjects, three in the red group, four in the white group, and four in the blue group. Two subjects were lost to follow-up, one each from the red and white groups. Statistical analysis including one-way analysis was done with the means, Wilcoxon/Kruskal-Wallis, and one-way analysis tests.

The results showed a similar weight gain pattern between the three groups, with an average of 2.8 lbs gained in the red group, 2.4 lbs gained in the white group, and 2.6 lbs gained in the blue group. The average HDL levels decreased by 1.00 mg/dL in the red group (standard deviation (SD) 2.82843), increased by 2.00 mg/dL in the white group (SD 8.88819), and increased by 5.75 mg/dL in the blue group (SD 8.01561). The HDL:total cholesterol ratios decreased by 0.00748 in the red group (SD 0.002660), an average of 0.04053 in the white group (SD 0.028138), and an average of 0.01614 in the blue group (SD 0.023808).

The results suggest that both chia seeds and oatmeal may be good dietary sources to naturally increase HDL cholesterol, more substantially so with the diet including chia seeds, but may or may not improve total cholesterol:HDL ratios. The effect of weight gain is unclear, as all groups gained weight similarly. Hence, further study is warranted.