The claim that protein is bad for you goes back to the last century, when it was assumed that nitrogen and ammonia produced during protein digestion and breakdown (1) were bad for your health. The negative light on protein is also cast by cohort studies that show a correlation between protein intake, CVD (2) and kidney disease (3, 13) in the general population.

However, with the advent of sports nutrition research in the last 20-30 years, this thesis is not a modern position in nutrition and has been refuted numerous times in randomized controlled trials (RCTs) and meta-analyses (4, 5, 6, 7, 8, 16, 17).

Effects of Protein on Sports

A high protein diet, defined by the International Society of Sports Nutrition (ISSN) as 1.4-2.0 g protein/kg body weight in sports, has been well established as a safe and effective diet for achieving athletic performance (9). Dietary protein, in addition to its role in muscle hypertrophy (9, 10), also plays a role in satiety (11), fat loss, and muscle mass maintenance on a hypocaloric diet (12). Therefore, protein intake recommendations for active individuals are higher than the 0.8 g/kg recommended for the average person.

Bones and Protein

Contrary to another belief that protein has a negative effect on bone and calcium loss, increasing protein to as little as 0.75 g/kg has been shown to improve bone markers in older adults (14). Overall, there is no scientific evidence linking higher protein intakes with adverse outcomes in healthy, athletic individuals (9). On the other hand, excessively high (2.4 g/kg) protein intake over a long period of time (several months) may result in insufficient intake of other nutrients, including calcium, which in turn will lead to bone loss. Thus, the ISSN position is that active older adults need protein intakes in the range of 1.4 to 2.0 g/kg, and that this intake level is safe (9).

Why is there still an anti-protein agenda in medicine?

Indeed, there is a link between protein intake and health problems in cohort studies (3, 13, 15). However, it is true for people with already existing kidney (3) and heart (13) diseases. The fundamental problem with cohort studies on the general population, is the logical fallacy of ‘association does not mean causation’ and should not be extrapolated on individual level as they are presented, but rather used to find trends and associations. It is likely that the average person with protein also consumes more fat, salt and generally has an unbalanced diet (15). Furthermore, in the same studies (3), low protein intake (<60 g per day) had a pronounced negative effect on health and overall mortality. 

Looking at randomised controlled trials (RCTs) that look more at the individual level, the picture is more clear. Two meta-analyses, which together reviewed more than 200 RCTs, show that increasing protein in controlled conditions leads only to positive effects on the body, such as increasing muscle mass, lowering blood triglycerides and lowering blood pressure (16, 17).

Recommendations

For average people, recommendations of 0.8 g per kg of body weight remain preferable, because low awareness of nutrition and nutritional science in the population can lead to insufficient intake of other nutrients with a poorly planned high-protein diet that can drag the increase in fat and salt intake. For athletes of any kind of sports, especially strength sports, the recommendations are 1.4-2.0 g/kg of dietary protein. It should be emphasized that the total protein is taken into account, including from plant sources, and not only from animals.

Sodium is mainly found in table salt. It is an essential nutrient required to maintain plasma volume, acid-base balance, transmission of nerve impulses, and normal cell function [1, 7]. Sodium performs many physiological functions, including the absorption of nutrients and the maintenance of fluid balance - osmolarity.

Salt and public health

Studies on the general population find that sodium excess is strongly associated with certain health risks, such as high blood pressure – hypertension [3, 4, 5]. For this reason, WHO has established recommendations for daily consumption of no more than 2.3 g of sodium or 5 g of salt (table salt is 40% sodium) [1]. Indeed, most people with a sedentary lifestyle consume as much as 9-12 g of salt per day from processed foods. For example, one Big Mac contains 2.3 g of salt [9], and 4 slices of bacon contain 1.7 g [10]. Such people may benefit from reducing their salt intake, especially if they are elderly and have hypertension, any other diseases associated with kidneys (e.g. renal dysfunction) or blood vessels (e.g. cardiovascular disease; CVD).

In addition, the trends indicate that people consume less vegetables and fruits, which leads to potassium deficiency [1]. This increases the fluid imbalance between the intra- and extra-cellular environment, because sodium and potassium play a major role in this process [13]. Therefore, reducing salt intake is the most cost-effective and effective method for combating hypertension and can save 2.5 million lives annually [1] (for a detailed analysis of the diet for lowering blood pressure, the reader is referred to the DASH diet [6])

The need for salt in sports

While such recommendations apply to the general population, they are not suitable for healthy active people, and especially athletes.

An athlete can expend about 1.3 g of salt with sweat for every pound (0.45 kg) lost during high-intensity exercise [8] or 2.5 g of salt per hour; however, the exact amount of sweat and sodium lost during activity varies greatly between individuals and can also depend on the type of activity, air temperature, altitude and individuals’ thermal regulation.

However, athletes should consume more sodium/salt than the WHO recommends because sodium deficiency can lead to chronic fatigue, heart failure due to low plasma levels, seizures, dehydration, as well as epilepsy and death [7].

Salt = harm. Myth or truth?

The expression "Everything in moderation" is perfect here. Salt is critical for the body, but its excess can lead to problems in some cases.

The exact recommended amount depends on the level of activity and diet and genetics. Some people who sweat a lot lose sodium through sweat faster than others. It is not worth taking separate measurements of sodium loss unless you are a professional athlete (but you can read about measurement methods here [12].

Also, there are people who react to sodium consumption differently, where one will immediately have an increase in blood pressure (responders), and the other will not have such an effect (non-responders) [11].

How much salt should I consume?

Therefore, if you are not hypertensive, your blood pressure does not fluctuate, and you regularly engage in physical activity, then your salt consumption should be from 5g and above. Pay attention to the symptoms of sodium deficiency and excess, described above.

On the contrary, if there are predispositions such as hypertension, CVD, and you are elderly, then salt intake should be < 5g or < 2.3g sodium per day, and perhaps even lower – 1.5g sodium/day [7]. Such individuals are advised to consult a specialist and follow the DASH diet.

The history of fats

For about 40 years, there has been an anti-fat agenda in the food industry, where fats from food are blamed for cardiovascular diseases (CVD).

The hypothesis is based on the following dogmas:

a) fats contain more calories per gram (9 kcal / g) than proteins and carbohydrates (4 kcal / g). Therefore, overconsumption of calories is more likely with a high-fat diet.

b) fats - especially saturated ones - contain cholesterol, and high cholesterol in the blood is the cause of CVD.

For these reasons, palm oil, which is 50% saturated fats (1), is an “undesirable” product in the human diet. Despite this, palm oil remains the most common oil used in the food industry (2). Why is that?

Fats and CVD

Going into the details of the latest research, it becomes clear that the stigma of fats and their association with CVD is not a modern view of healthy eating. A meta-analysis that included 347,747 subjects from cohort studies showed no direct association between saturated fats and CVD (3). In addition, the authors of a 2018 systematic review of the association between palm oil and CVD conclude: ”The current review cannot provide convincing evidence for or against palm oil consumption regarding the risk and mortality of cardiovascular diseases.” (4). However, the association between high fat intake and mortality remains consistent in modern studies (5). It can be concluded that fats, including saturated fats, do not “cause” diseases in themselves, but can contribute to their development.

Why is palm oil found in many products?

There are several reasons:

- Palm oil cultivation is a very efficient process. A hectare of palm oil plantation can produce 3.3 tons of oil, while a hectare of sunflowers produces only 0.7 tons (6).

- Palm oil is an extremely versatile oil. It is resistant to oxidation, so it can extend the shelf life of foods; it is stable at high temperatures, so it helps give fried foods a crispy texture;

Ethical Issue

Palm oil is produced from the Elaeis guineensis plant, which grows in Africa. Due to high global demand for palm oil, the plant has been grown in countries such as Malaysia, creating over 490,000 jobs and increasing GDP (7). However, this trend has also had negative consequences, including the clearing of healthy forests for palm plantations. This, in turn, provokes changes in the ecosystem and the extinction of animals such as orangutans (8). In addition, the production of palm oil increases carbon dioxide emissions, and the workers are often children. For these reasons, The Roundtable on Sustainable Palm Oil (RSPO) was created to make production as environmentally friendly and ethically acceptable as possible.

Benefits

Human studies show that vitamin E in palm oil can help protect delicate polyunsaturated fats in the brain (9), slow the progression of dementia (10), reduce the risk of stroke (11), and prevent the growth of brain lesions (12).

In the food industry, palm oil is used mainly to replace animal fats and trans fats (13).

Conclusion

Palm oil is a very versatile product that does not contain any unique harmful effects than any other fats. The main complaints about palm oil are its high fat content and the moral aspects of its production. An adequate diet and the purchase of products with the RSPO label will help to avoid the above-mentioned problems and get only the beneficial properties of the oil.

Omega-3 fatty acids, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are widely recognized as essential nutrients for human health (1).

Increasing EPA and DHA intake has been linked to a wide range of health benefits, such as the development and function of nerve and eye tissue, as well as a reduced risk of heart disease, inflammation, depression, and other chronic conditions (1, 2, 3, 4, 5, 6).

Fish is the primary dietary source of omega-3s for humans, as well as a source of protein, vitamins, and minerals. It is recommended to consume at least two servings of fish per week, one of which should be fatty-oily (7).

Due to the growing global population and its demand for seafood, coupled with wild catches, most fish are farmed. Indeed, aquaculture has been the fastest growing food production sector over the past few decades (8). Today, salmon farming occurs worldwide, with Norway, Chile, Scotland, and North America being the main producers, with a combined production of about 2 million metric tons (9).

🐟 Wild vs. Farmed Salmon

In aquaculture, vegetable oils are increasingly being used in salmon feeding (10). That’s considered to be the problem, because the fatty acid profile of vegetable oils differs from wild fish, as they are richer in omega-6 and lack omega-3, leading to changes in the fatty acid composition of farmed fish.

One common misconception is that farmed fish is inferior in quality and nutrition to wild fish. In fact, farmed fish have been found to contain as many or more grams of EPA + DHA per serving than their wild-caught counterparts (9, 12, 13, 14). How is that possible?

Between 2006 and 2015, the proportion of EPA and DHA in fish lipids dropped significantly from ~24% to 13.0% (9), which at first glance might lead one to believe that wild salmon is better for humans in terms of omega-3s. However, in absolute terms (i.e., grams of EPA + DHA per 100 g), farmed salmon contains significantly more EPA + DHA, providing 1,360 mg compared to 760 mg per 100 g for wild salmon (9).

This is because farmed salmon consume significantly more food than wild salmon, leading to an increase in their total fat mass (9). Therefore, per serving size, farmed salmon contains more fat, and therefore more EPA and DHA, than wild salmon.

📊 Conclusion

☑️ Farmed salmon is fattier than wild salmon.

☑️ Farmed salmon contains more omega-3s per wet weight serving than wild salmon.

☑️ Farmed salmon is an excellent source of EPA and DHA. To meet the recommendations of 250-500 mg EPA + DHA, a person should consume 2 servings (140 g) of fish per week, where one of them should be oily.