Paul Saladino MD questions plant-based diets for longevity. What does the science say?

2. Why might a plant-based diet support longevity?

After listing several nutrients found in animal products, Saladino asks the question: “why are we being told plant-based diets are best for longevity?” Saladino looks at those nutrients in isolation, but the answer to his question should address the role of the whole diet for overall health and well-being. 

Nutritional guidelines are guided by years of research and accumulated data. This is what leads to advice such as that to increase consumption of plants to support better health. For example, meta-analyses offer robust evidence to inform nutritional guidelines, because they combine data from numerous, relevant studies to answer specific questions. In a review published in Critical Reviews in Food Science and Nutrition, researchers examined and summarised a few available meta-analyses looking into the links between nutrition and longevity. The authors found that eating more whole grains, vegetables, fruits, nuts, and coffee was associated with living longer, while a high intake of red and processed meat was related to an increased risk of early death. Following eating patterns like the Mediterranean diet also lowers this risk.

In her book, The Science of Plant-Based Nutrition, Registered Nutritionist Rhiannon Lambert looks at the research surrounding plant-based nutrition. She summarises the benefits as follows:

• Reduced Risk of Heart Disease
• Reduced Diabetes Risk
• Lower Rates of Obesity
• Better Gut Health

These benefits mainly stem from an increased intake of fibre, combined with a reduced consumption of saturated fat. Together, the above benefits can contribute to an increased life span, although other important factors such as healthcare access, genetics and environment also come into play. 

3. What the post overlooks

According to Saladino, the most essential nutrients for longevity are Vitamin A, B12 and K2; H-Iron; Taurine; Creatine; Carnosine; Anserine; and 4-hydroxiproline. By focusing solely on this group of nutrients, Saladino’s post leaves out a list of other essential nutrients, minerals and fatty acids which might not be abundant or present in animal-based foods. His list also leaves out the role of dietary fibre, which has recently come to the foreground of nutritional research. Dietary fibre is crucial for gut health, supporting digestion, and reducing the risk of chronic diseases like heart disease and diabetes. 

Secondly, the list of nutrients shared by Saladino is predominantly (but not exclusively) found in animal products, particularly organ meats and muscle tissues. These are also the foods which Saladino regularly promotes on his platform. But what is also left out is the important role of balance to support health. The foods which Saladino promotes to support longevity are mostly foods which are also high in saturated fat. It is well understood that a diet high in saturated fats can raise LDL-Cholesterol, increasing risks of heart disease and stroke.

‍Why do these considerations matter? Many people’s diets are too high in saturated fats, and deficient in fibre. As a result, the general advice to make foods high in saturated fats the foundation of one’s diet without considering individuals’ health backgrounds can be problematic.

Finally, the post ignores the existence of cultures around the world where plant-forward diets are the norm and are positively associated with longevity and good quality of life. The Mediterranean diet is one example.

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4. So, can you be on a 100% plant-based diet and meet all nutritional requirements?

Yes, as long as you ensure a reliable source of certain micronutrients such as B12, which can be obtained through supplements and fortified foods. According to Registered Nutritionist Rhiannon Lambert, “certain needs cannot be met by eating plants alone so you may need to consider supplementation and, in particular, vitamin B12, iodine, iron, calcium, and omega-3.” This would ensure getting the health benefits from plants while avoiding deficiencies.

Let’s finish by taking a closer look at the list of nutrients shared by Saladino, which he claims are not found in plant foods: 

‍Vitamin A - Found in the form of beta-carotene (provitamin A), which is converted to active vitamin A in the body. Think “orange foods” like carrots, sweet potatoes, pumpkin or squash. Other rich sources include spinach and other leafy greens.

‍Vitamin B12 - It is true that B12 is not naturally present in plant foods. It is synthesised by bacteria and found in animal products or fortified foods and supplements. Supplements and fortified foods make it possible to obtain B12 on a plant-based diet. 

‍Vitamin K2 - Found in animal products and fermented foods (e.g., natto, a plant-based food). Sauerkraut is another source. K1 (from plants) can also be converted to K2 in the body, though conversion rates vary.

‍Heme Iron (H-Iron) - While heme iron is found in animal products, non-heme iron is abundant in plant foods like legumes, tofu, seeds, and leafy greens. Consuming it with vitamin C boosts absorption.

‍Taurine - Taurine is found in animal products but is not essential, as the body can synthesise it from other amino acids (methionine and cysteine).

‍Creatine - Creatine is present in animal tissues but is non-essential because the body produces it from amino acids like arginine, glycine, and methionine.Carnosine - Found in animal products but is also non-essential, as the body synthesises it from beta-alanine and histidine.

‍Anserine - Found in animal tissues. Like carnosine, it is non-essential and not required in the diet.

‍4-Hydroxyproline - Found in collagen (animal products). The body can synthesise it from proline, which is derived from plant or animal proteins.

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While some nutrients listed are predominantly found in animal products, many are non-essential, as the human body can produce them from precursors found in plant foods. The claim that none of these nutrients are in plant foods or that plant-based diets are not good for longevity is misleading. With proper planning and supplementation (e.g., B12), a plant-based diet can support optimal health and longevity.

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We have contacted Paul Saladino and are awaiting a response.

‍Disclaimer:
This fact-check evaluates the claims made in Dr. Saladino’s post based on current evidence in nutritional science and public health guidelines. It does not aim to promote or discredit specific dietary patterns but to provide clarity on the relationship between diet, nutrients, and longevity. Individual dietary needs vary, and it is always advisable to consult with a registered dietitian or healthcare professional for personalised nutritional advice.