Rethinking Salt, Fat, and Cholesterol: Balancing Nutritional Needs with Health Risks

Rethinking Salt, Fat, and Cholesterol: Balancing Nutritional Needs with Health Risks

By Francis Akenami, BMLS, PhD, FIMLS

In recent years, research on salt, fats, and cholesterol has prompted a reevaluation of longstanding dietary recommendations. Let’s go through some points based on the latest findings and perspectives from major health organizations.

Salt and Health: Lancet’s Position

The Lancet published research by Dr. Andrew Mente and others suggesting that moderate salt intake (around 3-5 grams per day) might be associated with a lower risk of cardiovascular events compared to very low or high levels (Mente et al., 2018). This goes against the American Heart Association’s (AHA) recommendation to keep salt intake at or below 2.3 grams per day (American Heart Association, 2021) . However, the Lancet’s findings did not broadly advocate for high salt intake; rather, they highlighted a potential “optimal” range where both very low and high salt levels might increase health risks. The AHA criticized these findings, arguing that excessive salt intake remains a risk factor for hypertension, which is closely related to stroke and heart disease .

Dietary Fat and Cholesterol

Historically, dietary fat was thought to be a primary cause of high cholesterol levels, contributing to cardiovascular diseases. Recent studies, however, have refined this perspective, highlighting that not all fats have the same impact on cholesterol. For example, while saturated fats and trans fats can increase LDL (bad) cholesterol, unsaturated fats may help maintain or even improve cholesterol levels (Sacks et al., 2017) . The AHA has since updated its guidelines, focusing on a balanced intake of healthy fats rather than avoiding all fats altogether .

Cholesterol’s Role in Hormone Production

Cholesterol is essential for the body, serving as a building block for steroid hormones, including estrogen, testosterone, and cortisol. Low cholesterol levels can theoretically impact hormone production, which may affect sexual function and mood regulation. Cholesterol is also necessary for creating serotonin receptors in the brain, which play a role in mood regulation, suggesting that balanced cholesterol is crucial for both mental and physical health (Cerqueira et al., 2022).

Sodium-Potassium Pump and Kidney Function

Salt (sodium chloride) is vital for the sodium-potassium pump, which is essential for cellular function and kidney health. Sodium levels impact fluid balance, nerve transmission, and muscle function. However, while sodium is essential, excessive intake can lead to high blood pressure and kidney strain, particularly in those who are sensitive to salt (Giebisch, 2017) .

Recommended Salt Intake

The Lancet’s research suggests a moderate salt intake (around 3-5 grams/day) as potentially optimal for cardiovascular health, while the AHA and WHO recommend no more than 2.3 grams daily for most adults (WHO, 2012) . The discrepancy arises from different interpretations of population-based studies versus clinical findings, fueling ongoing debate.

Thoughts on Moderation

While too little salt can impair bodily functions, excessive intake also poses health risks. For fats, a diet rich in unsaturated fats with limited trans and saturated fats seems optimal. Individual health needs and personal risk factors should guide dietary choices, ideally with input from healthcare providers.

References:

1. Mente, A., O’Donnell, M., Rangarajan, S., et al. (2018). “Associations of urinary sodium excretion with cardiovascular events in individuals with and without hypertension: A pooled analysis of data from four studies.” The Lancet, 392(10146), 465-475. DOI: 10.1016/S0140-6736(18)31376-X
2. American Heart Association (2021). “How Much Sodium Should I Eat Per Day?” Heart.org. Retrieved from https://www.heart.org.
3. Sacks, F. M., Lichtenstein, A. H., Wu, J. H., et al. (2017). “Dietary Fats and Cardiovascular Disease: A Presidential Advisory from the American Heart Association.” Circulation, 136(3), e1-e23. DOI: 10.1161/CIR.0000000000000510
4. Cerqueira, C. C. S., et al. (2022). “Cholesterol and Steroid Hormone Synthesis: Metabolic Interactions and Clinical Implications.” Endocrine Reviews, 43(3), 381-409. DOI: 10.1210/endrev/bnab037
5. Giebisch, G. (2017). “The Sodium Potassium Pump and Cellular Function.” Physiological Reviews, 97(1), 107-119. DOI: 10.1152/physrev.00010.2016
6. World Health Organization (2012). “Guideline: Sodium intake for adults and children.” Geneva: World Health Organization. Retrieved from https://www.who.int.