Personally, I have stopped getting into discussions about nutrition online, because it is time consuming and frustrating.
But I know that a lot of people get into these arguments often, so I've decided to write an article to give people some "weapons" to win these arguments easily.
By far the best way to win a nutrition discussion is to have a link to a good Scientific study. Nutrition is science, after all, although it often resembles religion or politics.
If you are ever in a discussion with someone who has outdated nutrition views, do not hesitate to use the answers and studies listed below.
Be sure to check this page if you tend to appear in this type of argument often!
"The best diet is a diet low in fat, with carbohydrates at 50-60% of calories"
Reply: The low-fat diet has been tested in several huge randomized controlled trials. It does not cause any weight loss over a period of 7.5 years and, literally, has no effect on heart disease or cancer.
The low-fat diet is a great failure. All the main studies show that it does not work.
- Howard BV, et al. The low-fat dietary pattern and weight change over 7 years: the trial of dietary modification of the Women's Health Initiative. Journal of the American Medical Association, 2006.
- Howard BV, et al. Dietary pattern low in fat and risk of cardiovascular disease. Journal of the American Medical Association, 2006.
Intervention study of multiple risk factors: changes in risk factors and mortality outcomes. Journal of the American Medical Association, 1982.
Plus: Show them this article.
"Sugar is bad for you, but only because they are empty calories"
Reply: The harmful effects of sugar go beyond empty calories. When consumed in excess, it can cause serious harmful effects on the metabolism and cause insulin resistance, fatty liver disease and other metabolic disorders.
Studies show that in the long term, a high consumption of sugar is strongly associated with the risk of obesity, type II diabetes, heart disease and even cancer.
- Stanhope KL, et al. The consumption of fructose-sweetened beverages, not sweetened with glucose, increases adiposity and visceral lipids and decreases insulin sensitivity in overweight or obese humans. Clinical research journal, 2009.
- Stanhope KL, et al. Adverse metabolic effects of fructose in the diet: results of recent epidemiological, clinical and mechanical studies. Current opinion on lipidology, 2013.
- Ludwig DS, et al. Relationship between the consumption of sugary drinks and childhood obesity: a prospective and observational analysis. The lancet, 2001.
- Schulze MB, et al. Sugary drinks, weight gain and incidence of type 2 diabetes in young and middle-aged women. Journal of the American Medical Association, 2004.
- Bostick RM, et al. The consumption of sugary drinks and the risk of coronary heart disease in women. Causes and control of cancer, 1994.
- Fung TT, et al. The consumption of sugar, meat and fat, and non-dietary risk factors for the incidence of colon cancer in Iowa women. The American Journal of Clinical Nutrition, 2009.
Plus: Even more studies here.
"Eggs increase cholesterol and lead to heart disease"
Reply: The cholesterol in the eggs does not raise the "bad" cholesterol in the blood. HDL cholesterol increases (the "good") and eggs actually improve the lipid profile in the blood.
Studies show that egg consumption is not associated with heart disease. Whole eggs are among the most nutritious foods on the planet.
- Rong Y, et al. Egg consumption and risk of coronary heart disease and cerebrovascular accident: dose-response meta-analysis of prospective cohort studies. British Medical Journal, 2013
- Fernandez ML. Dietary cholesterol provided by eggs and plasma lipoproteins in healthy populations. Current opinion on clinical nutrition and metabolic care, 2006.
- Blesso CN, et al. Whole egg consumption improves lipoprotein profiles and insulin sensitivity to a greater extent than egg substitute without yolk in individuals with metabolic syndrome. Metabolism, 2013
Plus: Details on the health benefits of eggs and more studies here.
"The protein is bad for the kidneys"
Reply: It is often claimed that a high protein intake can cause kidney damage, but this is false. While it is important for people with pre-existing kidney disease to reduce protein, the same is not true for people with healthy kidneys.
Studies show that a high protein intake has no detrimental effects on kidney function in healthy people, not even bodybuilders who eat large amounts of protein.
- Manninen AH. Weight loss diets with high protein content and putative adverse effects: Where is the evidence? Magazine of the International Society of Sports Nutrition, 2004.
- Martin WM, et al. Protein intake in the diet and renal function. Nutrition and Metabolism, 2005.
"Saturated fats increase cholesterol and cause heart disease"
Reply: This is a myth. Saturated fat raises HDL (the "good") cholesterol and changes LDL from small to dense LDL, which is benign and does not increase the risk of heart disease.
This has been studied intensively in recent decades and studies consistently show that saturated fat is not related in any way to the risk of heart disease.
- Siri-Tarino PW, et al. Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. The American Journal of Clinical Nutrition, 2010.
- Mind A, et al. A systematic review of the evidence supporting a causal link between dietary factors and coronary heart disease. Archives of Internal Medicine, 2009.
- Dreon DM, et al. The change in the intake of saturated fats in the diet correlates with the change in the mass of large particles of low density lipoproteins in men. The American Journal of Clinical Nutrition, 1998.
Plus: The myth of saturated fats has been thoroughly disproved here and here.
"Low carb diets are not healthy"
Reply: This is simply not true. Since 2002, low-carbohydrate diets have been widely studied and more than 20 randomized controlled trials have been conducted.
Consequently, they lead to much better health outcomes than the typical low-fat diet. They cause more weight loss and improve all the major risk factors of the disease, including triglycerides, HDL and blood sugar levels.
- Westman EC, et al. Nutrition and metabolism low in carbohydrates. American Journal of Clinical Nutrition, 2007.
- Hession M, et al. Systematic review of randomized controlled trials of low carbohydrate diets versus low fat / calories in the management of obesity and its comorbidities. Reviews of obesity, 2008.
- Santos F, et al. Systematic review and meta-analysis of clinical trials of the effects of low-carbohydrate diets on cardiovascular risk factors. Obesity Reviews, 2012.
Plus: Many more studies and a complete review of science here.
"Red meat is not healthy and should only be eaten in moderation"
Reply: It is true that the consumption of processed meat is associated with an increased risk of many diseases, but not the same with unprocessed red meat.
Unprocessed red meat is harmless, although it can form harmful compounds if it is cooked in excess. The answer is not to avoid red meat, but make sure not to burn it.
The association between unprocessed red meat and cancer is very exaggerated, the large review studies show that the effect is very weak in men and non-existent in women.
- Micha R, et al. The consumption of red and processed meat and the risk of coronary heart disease, stroke and diabetes mellitus: a systematic review and a meta-analysis. Circulation, 2010.
- Rohrmann S, et al. Meat consumption and mortality: results of European prospective research on cancer and nutrition. Medicine BMC, 2013.
- Alexander DD, et al. Meta-analysis of prospective studies of red meat consumption and colorectal cancer. European Journal of Cancer Prevention, 2011.
- Alexander DD, et al. Red meats and colorectal cancer: a critical summary of prospective epidemiological studies. Reviews of obesity, 2011.
Plus: More studies on red meat here.
"Protein is bad for bones and causes osteoporosis"
Reply: Although it is true that the protein can cause the loss of calcium from bones in the short term, this effect does not persist in the long term.
In fact, studies consistently show that the protein actually improves bone health in the long term, NOT the other way around. Therefore, it is likely that the terrible advice of keeping the protein low increases the risk of osteoporosis.
- Kerstetter JE, et al. Dietary proteins and skeletal health: a review of recent research in humans. Current opinion on lipidology, 2011.
- Bonjour JP. Dietary proteins: an essential nutrient for bone health. The Journal of the American College of Nutrition, 2005.
- Munger RG, et al. Prospective study of dietary protein intake and the risk of hip fracture in postmenopausal women. The American Journal of Clinical Nutrition, 1999.
"People should reduce sodium consumption"
Reply: Although sodium restriction can lower blood pressure, it does not seem to reduce the risk of heart disease or death.
Some studies even show that if you restrict too much sodium, you can increase some disease risk factors.
There is no science behind the recommendation of 1500-2300 mg per day and people who are healthy can eat "normal" amounts of sodium without any harm.
- Taylor RS, et al. Reduced dietary salt for the prevention of cardiovascular diseases. Cochrane Database of Systematic Reviews, 2011.
- Jurgens G, et al. Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterols and triglycerides. Cochrane Database of Systematic Reviews, 2003.
- Garg R, et al. Low salt diet increases insulin resistance in healthy subjects. Metabolism, 2011.
Plus: Many more studies on the sodium myth here and here.
"Polyunsaturated fats reduce cholesterol and reduce the risk of heart disease"
Reply: There are two types of polyunsaturated fats, Omega-3 and Omega-6. It is true that omega-3 reduces the risk of heart disease, but not the same with omega-6.
Although Omega-6 (soybean oil, corn oil, etc.) can lower cholesterol, studies show that it actually increases the risk of heart disease.
Therefore, the horrible advice to increase polyunsaturated fat, regardless of the type, probably contributes to heart disease instead of preventing it.
- Ramsden CE, et al. Use of linoleic acid in the diet for the secondary prevention of coronary heart disease and death. British Medical Journal, 2013
- Lands WE, et al. Dietary fat and health: evidence and prevention policy: the careful use of dietary fats can improve life and prevent diseases. Annals of the Academy of Sciences of New York, 2005.
- Ramsden CE, et al. Dietary interventions with specific n-6 and mixed polyunsaturates have different effects on the risk of coronary heart disease: a meta-analysis of randomized controlled trials. British nutrition magazine, 2010.
Plus: Many more studies on vegetable oils here.
"People should choose low-fat dairy products to reduce calories and saturated fat"
Reply: There is no evidence that people benefit from choosing low-fat dairy products instead of full fat. In addition, low-fat dairy products are generally high in sugar, which makes this wrong advice seriously questionable.
Dairy products filled with fat (especially grass-fed cows) contain many important nutrients such as vitamin K2 and butyrate, which are very rare in the diet.
High-fat dairy products are actually associated with a lower risk of obesity. In countries where cows are largely grass-fed, people who consume dairy products with higher fat content have a drastically reduced risk of heart disease.
- Kratz M, et al. The relationship between the consumption of high-fat dairy products and obesity, cardiovascular and metabolic diseases. European Nutrition Magazine, 2013.
- Bonthius M, et al. Dairy consumption and mortality patterns of Australian adults. European Journal of Clinical Nutrition, 2010.
- Smit, et al. Conjugated linoleic acid in adipose tissue and risk of myocardial infarction. The American Journal of Clinical Nutrition, 2010.
"Weight loss is all about calories and calories out"
Reply: This is completely false, different sources of calories go through different metabolic pathways in the body and have different effects on hunger, hormones and the brain.
Also, do not forget that health is much more than weight. Certain sources of calories (added sugar, vegetable oils) can cause harmful effects on the metabolism that have nothing to do with their caloric value.
- Feinman RD, et al. "A calorie is a calorie" violates the second law of thermodynamics. Nutrition Diary, 2004
- Johnston CS, et al. The postprandial thermogenesis is increased by 100% in a high protein diet and low in fat compared to a diet high in carbohydrates and low in fat in young and healthy women. The Journal of the American College of Nutrition, 2002.
- Veldhorst MA, et al. The presence or absence of carbohydrates and the proportion of fat in a high protein diet affects suppression of appetite, but not the expenditure of energy in human subjects of normal weight fed with energy balance. British nutrition magazine, 2010.
Plus: Many more studies on the myth of calories here.
"It is better to eat many small meals throughout the day"
Reply: It is a myth that it is better to eat many small meals instead of several large meals. Studies show that it has no effect on health or body weight.
- Bellisle F, et al. Frequency of meals and energy balance. British nutrition magazine, 1997.
- Cameron JD, et al. The increase in the frequency of meals does not promote greater weight loss in subjects who were prescribed a diet of 8 weeks of energy with restricted energy. British nutrition magazine, 2010.
Plus: A deep discredit of this myth here.
"Fat makes you fat"
Reply: Although fat has more calories per gram than carbohydrates and proteins, it no longer makes you fatter. Eating foods that are naturally high in fat tends to reduce appetite.
Studies consistently show that diets that are high in fat (but low in carbohydrates) lead to a much greater weight loss than diets that are low in fat.
- Brehm BJ, et al. A randomized trial that compared a very low-carbohydrate diet and a low-calorie diet with caloric restriction on body weight and cardiovascular risk factors in healthy women. The Journal of Clinical Endocrinology & Metabolism, 2003.
- Yancy WS, et al. A low-carbohydrate ketogenic diet versus a low-fat diet to treat obesity and hyperlipidemia: a randomized, controlled trial. Annals of Internal Medicine, 2004.
- Westman EC, et al. The effect of a low carbohydrate ketogenic diet versus a low glycemic index diet in glycemic control in type 2 diabetes mellitus. Nutrition and Metabolism, 2008.
Reference: https: //www.healthline.com/nutrition/how-to-win-an-argument-with-a-nutritionist