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Recommendations Summary

DLM-SF: Replacement of Saturated Fat Intake 2023

Click here to see the explanation of recommendation ratings (Strong, Fair, Weak, Consensus, Insufficient Evidence) and labels (Imperative or Conditional). To see more detail on the evidence from which the following recommendations were drawn, use the hyperlinks in the Supporting Evidence Section below.


  • Recommendation(s)

    DLM-SF: Replacement of Saturated Fat Intake

    In adults living with and without cardiovascular disease, healthcare professionals should recommend replacing dietary saturated fat intake with dietary polyunsaturated fat intake. Replacement of dietary saturated fat with polyunsaturated fat promotes healthy eating patterns and reduces total cholesterol and coronary heart disease events; however, there was no significant effect on all-cause, cardiovascular disease, or coronary heart disease mortality. 

    Rating: Level 1(B)
    Imperative

    • Risks/Harms of Implementing This Recommendation

      Recommendations to reduce saturated fat intake may inadvertently have potential risks and harms in some populations as implementation of this recommendation may not be accessible to underserved and vulnerable populations. Underserved and vulnerable populations are populations that face health, financial, educational, and/or housing disparities (Serving Vulnerable and Underserved Populations. Accessed January 17, 2023). Access to supermarkets and convenience stores that have a variety of foods is known to be limited in neighborhoods with high minority populations and low population density, which could limit access to lower saturated fat food choices (Larson 2009). Underserved and vulnerable populations with limited health literacy may not have access to nutrition education and resources that would facilitate making this change. Food insecurity may also serve as a potential barrier to following this guideline, as provision of adequate food and nutrients may take priority. When overall access to adequate food is a challenge, efforts to reduce saturated fat intake may result in subsequent reduction in other vital nutrients, such as iron, calcium, vitamin, vitamin B12, and protein, which could compromise the overall diet quality. Knowledge deficits regarding how to translate these recommendations into healthy meal choices may further contribute to health inequities. These challenges suggest that the populations who would most benefit from implementation of this guideline may not be able to follow through with the recommendations.

    • Conditions of Application

      Based on systematic reviews of the currently available evidence, a specific percentage of saturated fat reduction sufficient to impact outcomes could not be determined. However, the panel acknowledges that RDNs may desire some guidance when providing medical nutrition therapy to individuals who may benefit from saturated fat reduction. Hooper et al. 2020 conducted an analysis that compared the effect on the population consuming <10% of total energy from saturated fat compared to >10% of total energy from saturated fat and found greater reductions in cardiovascular disease events occurred at lower levels of saturated fat. However, these results were not statistically significant.

      An assessment by RDNs should include evaluation of anthropometrics, biochemical markers, medical history, as well as an individual's present eating habits, socioeconomic status, living conditions, cultural preferences, psychosocial and mental health status, and willingness/ability to make nutrition-related changes. Nutrition Care Process guidelines provide structure to document assessment and medical nutrition therapy recommendations. Nutrition recommendations should be tailored to the individual based on the interpretation of the assessment. This guideline supports the continuation of recommendations to limit total saturated fat intake to reduce the risk of cardiovascular disease events.

      At the population level, this guideline may also translate into the continued recommendation to limit saturated fat intake for cardiovascular health. Public health messaging and collaboration with the food industry and medical organizations and institutions can serve to promote this message.

      Additional information to promote reduction in saturated fat intake within heart-healthy dietary patterns can be found through the following professional organizations:

      Since recommendations to reduce saturated fat are already adopted by most healthcare organizations and professionals, barriers to implementing the recommendations in this guideline are predicted to be minimal. Many resources already exist to facilitate the promotion of a dietary pattern low in saturated fat, including the resources above. Promotion of dietary patterns that are low in saturated fat and include a healthy nutrient profile with regards to other eating behaviors would be an ideal way to align this guideline with practical approaches. The Mediterranean and Dietary Approaches to Stop Hypertension (DASH) dietary patterns are examples of dietary patterns that can be recommended to patients and clients to implement this guideline. 

      A potential barrier to this guideline implementation may be public confusion and frustration about the relationship between dietary-related factors and heart health. Public awareness of the shifting recommendations regarding an optimal dietary pattern for heart health may leave some hesitant to listen to any new recommendations, despite an ever-growing evidence base. Thus, consistent messaging among RDNs, other medical professionals, and public health organizations is crucial to helping build public confidence in using this guideline recommendation to facilitate dietary changes aimed at reducing CVD risk. 

    • Potential Costs Associated with Application

      Potential patient and consumer costs may include consultation with an RDN and the cost of grocery items to replace saturated fat intake with unsaturated fat alternatives. Costs may also include the development of educational materials for consumers and patients. 

      Cost for implementation into the healthcare organization should be minimal due to recommendation alignment with current practice. Investment in dissemination of this information within the professional community via further publications in professional journals and seminars at healthcare-related conferences would be beneficial for widespread awareness and implementation of this guideline.

    • Recommendation Narrative

      The recommendation is based on the results of an Evidence Analysis Center overview of systematic reviews with a total of four systematic reviews (Hamley 2017, Hooper et al. 2020, Mensink 2016, and Ramsden et al. 2016).

      Based on three systematic reviews, no significant association was found between replacement of saturated fat with polyunsaturated fat, monounsaturated fat, or carbohydrate intake and all-cause mortality (Hamley 2017, Hooper et al. 2020, Ramsden et al. 2016) or cardiovascular disease (CVD) mortality (Hooper et al. 2020) with low certainty evidence. Replacement of saturated fat with polyunsaturated fat was associated with a decrease in CVD events within the entire study population in the Hooper et al. 2020 systematic review with moderate certainty evidence. In Hooper et al. 2020, CVD events was a composite score of non-fatal myocardial infarction, angina, cerebral vascular accident, heart failure, peripheral vascular events, atrial fibrillation, and unplanned cardiovascular interventions (coronary artery bypass surgery or angioplasty). Evidence was limited for the effect of monounsaturated fat replacement on saturated fat, and carbohydrate replacement had limited to no effect. Hamley 2017 (systematic review of RCTs) identified clinical trials from earlier meta-analyses, then identified the trials as ‘adequately controlled’ or ‘inadequately controlled’ based on differences between the experimental or control groups. Subgroup analysis was then conducted for the adequately controlled and inadequately controlled groups. Hamley 2017 did not find an association between replacement of saturated fat with polyunsaturated fat and combined coronary heart disease (CHD) events when inadequately controlled trials were excluded from analysis. Hamley’s definition of CHD events was less clear: total CHD events were a combination of major CHD events (myocardial infarction and sudden death) and soft events (angina). 

      Hooper et al. 2020 found that replacement of saturated fat with polyunsaturated fat decreased total cholesterol and triglycerides. Mensink 2016 found an association between replacement of saturated fat with polyunsaturated fat and carbohydrates and reduced total cholesterol, LDL-C, and HDL-C levels.  Mensink 2016 (systematic review of clinical and observational trials) rated the quality of evidence for all the outcomes as high. However, considering the GRADE methods and after examining the data, the authors of this systematic review downgraded the quality of evidence to moderate, particularly due to the risk of bias of included studies. Ramsden et al. 2016 (systematic review of RCTs) found an association between replacement of saturated fat with polyunsaturated fat and reduced total cholesterol. Overall, certainty of evidence for blood lipids was moderate. 

      The panel took the evidence and all components of the Evidence-to-Decision framework into consideration when developing the nutrient replacement for the saturated fat recommendation. While there was no differential effect of replacement of saturated fat with polyunsaturated fat, monounsaturated fat, or carbohydrates on mortality, there was a reduction in cardiovascular disease events when saturated fat was replaced with polyunsaturated fat based on the results from the Hooper et al. 2020 systematic review. Replacement of saturated fat with polyunsaturated fat also resulted in a reduction in total cholesterol and triglycerides. Mensink 2016 found a reduction in total cholesterol, LDL-C, and triglycerides when saturated fat was replaced with polyunsaturated fat, monounsaturated fat, or carbohydrates. However, the Hooper et al. 2020 systematic review was rated higher quality per the AMSTAR II checklist, was published more recently, and had stricter criteria (limited to RCTs) compared to Mensink 2016 systematic review. Thus, the panel recommended polyunsaturated fat for replacement of saturated fat over monounsaturated fat and carbohydrates. 

      Download the summary tables for details:

    • Recommendation Strength Rationale

      • All-cause mortality: no effect based on low certainty evidence.
      • Cardiovascular mortality: no effect based on low certainty evidence.
      • Cardiovascular events: reduction based on moderate certainty evidence.
      • Coronary heart disease mortality: no effect based on low certainty evidence.
      • Blood lipids: reduction in total cholesterol and triglycerides based on moderate certainty evidence.

    • Minority Opinions

      None