Reducing saturated fat intake lowers LDL-C but increases Lp(a) levels in African Americans: the GET-READI feeding trial.
Study Goal
The researchers aimed to determine the effects of reducing dietary saturated fatty acids (SFA) on lipoprotein(a) [Lp(a)] levels and cardiovascular risk factors in African Americans.
Results Summary
Reducing SFA intake significantly lowered LDL-C and other lipid markers but unexpectedly increased Lp(a) levels in African Americans. The DASH-type diet (6% SFA) showed stronger effects than the average American diet (16% SFA).
Population
166 African Americans (70% women, mean age 35, mean BMI 28 kg/m²).
Effective Dosage
Two diets—37% total fat (16% SFA) vs. 25% total fat (6% SFA).
Duration
5 weeks per diet.
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
Reducing dietary saturated fatty acids (SFA) intake | decrease | low-density lipoprotein cholesterol (LDL-C) | across ethnicities | clinically significant | results in a clinically significant lowering | #1 |
dietary SFA reduction | neutral | Lp(a) levels | 166 African Americans | - | assessed the responses | #2 |
DASH-type diet | decrease | LDL-C | 166 African Americans | -12 mg/dl | reduced | #3 |
DASH-type diet | decrease | total cholesterol | 166 African Americans | -16 mg/dl | reduced | #4 |
DASH-type diet | decrease | HDL-C | 166 African Americans | -5 mg/dl | reduced | #5 |
DASH-type diet | decrease | apoA-1 | 166 African Americans | -9 mg/dl | reduced | #6 |
DASH-type diet | decrease | apoB-100 | 166 African Americans | -5 mg/dl | reduced | #7 |
DASH-type diet | increase | Lp(a) levels | 166 African Americans | 58 vs. 44 mg/dl | increased | #8 |
reductions in SFA intake | increase | Lp(a) levels | African Americans | significantly | significantly increased | #9 |
reductions in SFA intake | decrease | LDL-C | African Americans | - | reducing | #10 |
Reducing dietary saturated fatty acids (SFA) intake results in a clinically significant lowering of low-density lipoprotein cholesterol (LDL-C) across ethnicities. In contrast, dietary SFA's role in modulating emerging cardiovascular risk factors in different ethnicities remains poorly understood. Elevated levels of lipoprotein(a) [Lp(a)], an independent cardiovascular risk factor, disproportionally affect individuals of African descent. Here, we assessed the responses in Lp(a) levels to dietary SFA reduction in 166 African Americans enrolled in GET-READI (The Gene-Environment Trial on Response in African Americans to Dietary Intervention), a randomized controlled feeding trial. Participants were fed two diets in random order for 5 weeks each: 1) an average American diet (AAD) (37% total fat: 16% SFA), and 2) a diet similar to the Dietary Approaches to Stop Hypertension (DASH) diet (25% total fat: 6% SFA). The participants' mean age was 35 years, 70% were women, the mean BMI was 28 kg/m2, and the mean LDL-C was 116 mg/dl. Compared to the AAD diet, LDL-C was reduced by the DASH-type diet (mean change: -12 mg/dl) as were total cholesterol (-16 mg/dl), HDL-C (-5 mg/dl), apoA-1 (-9 mg/dl) and apoB-100 (-5 mg/dl) (all P < 0.0001). In contrast, Lp(a) levels increased following the DASH-type diet compared with AAD (median: 58 vs. 44 mg/dl, P < 0.0001). In conclusion, in a large cohort of African Americans, reductions in SFA intake significantly increased Lp(a) levels while reducing LDL-C. Future studies are warranted to elucidate the mechanism(s) underlying the SFA reduction-induced increase in Lp(a) levels and its role in cardiovascular risk across populations.