As part of the regular diet, the Institute of Medicine has established an adequate intake (AI) level for ALA of 1.6 grams for men and 1.1 grams for women. This represents the daily amount that is thought to be nutritionally adequate.[1] ALA is highly bioavailable in foods and oils, but flax and chia seeds should be ground before consumption to ensure the ALA is available for absorption.[2]
The optimal dosage for ALA as a supplement is not well established and is likely influenced by baseline levels of intake. For reducing triglycerides or LDL-cholesterol, a 2021 meta-analysis of RCTs found that ALA dosages of 3–8 grams daily were the most effective; however, the benefit on lipid levels was not observed beyond 3 months. Further complicating the issue is the form in which ALA is provided. In clinical trials, ALA is provided in a variety of ways, including as ALA-enriched margarine, in walnuts, in ground flax or chia seeds, or in their oils. Due to the heterogeneous nature of these dosage forms and the presence of other bioactive compounds, the consumption of, for example, 3 grams of ALA in walnuts may not produce the same effects as consuming 3 grams of ALA in flaxseed oil.