Following on from my last post on this topic, I thought I would do a follow up post with 10 other health and nutrition myths that you have likely been told are fact.
1. Dietary cholesterol and saturated fat cause heart disease.
If there’s one thing the media is good at, it’s scaring you away from perfectly innocent foods.
Eggs, red meat, butter and other foods have been demonised because despite being full of amazing, health promoting nutrients (especially egg yolks), they also contain high amounts of cholesterol and saturated fat. Eating food high in cholesterol and saturated fat doesn’t translate to increased cholesterol in your blood. And even if they did, research is starting to show that blood cholesterol levels alone are a relatively poor marker of heart disease risk.
The myth that saturated fat and cholesterol causes cardiovascular disease is not true. Food quality is what matters – there’s a big difference between eating a grass-fed steak and a fast food hamburger.
2. Eating fat makes you fat.
No, too many calories makes you fat.
For many decades, the traditional way to lose weight has been to subject oneself to a low-fat diet. But as studies pile on, old wisdom sometimes must give way. Today, we know that, just like eating cholesterol isn’t likely to increase your cholesterol levels, eating fat isn’t what makes you fat.
Far from being healthy, shunning all fat from your diet can be dangerous, since your body needs to consume at least some omega-3 and omega-6 fatty acids. As for saturated fat being the main driver of cardiovascular disease, as you have seen above, it is just another myth.
At the end of the day, trans fat is the only kind of fat that has been shown to be categorically detrimental to health — a little won’t kill you, but avoid it when you can.
3. Salt in the diet causes high blood pressure.
Most myths grow from a grain of truth. Studies have associated excess salt with hypertension (high blood pressure) kidney damage, and an increased risk of cognitive decline.
But salt (sodium) is an essential mineral; its consumption is critical to your health. The problem is when you consume too much of it.
Another issue is the source of all that salt. The average Australian eats an incredible amount of salty processed foods — which means that people who consume a lot of salt tend to consume a lot of foods that are generally unhealthy. That makes it hard to tease apart sodium’s effects from overall dietary effects. Except for individuals with salt-sensitive hypertension, who have rises in blood pressure from salt consumption. The evidence in support of low sodium intakes is much weaker than most people would imagine. As it stands, both very high and very low intakes are associated with cardiovascular disease.
Salt reduction is important for people with salt-sensitive hypertension, and excess salt intake is associated with harm. But drastically lowering salt intake has not shown much benefit in clinical trials. Most people will benefit more from a diet of mostly unprocessed foods than they would from micromanaging their salt intake.
4. Eating frequently increases your metabolic rate and is better for weight loss.
Digesting a meal does raise your metabolism by a little bit, but the only way to sustain this elevated rate is to eat more food, which in turn increases your caloric intake. The increased metabolic rate through digestion is negligible when compared against the actual caloric content of the food consumed.
Basically if you were to eat 3,000 calories spaced out over a few meals or 3,000 calories in one big meal, it makes no difference to your metabolism and makes no difference to your overall caloric intake. Therefore, the number of meals makes no difference in fat loss.
In fact, some studies suggest having smaller meals more often makes it harder to feel full, potentially leading to increased food intake.
Your metabolism can fluctuate based on the size of the meal, so fewer but larger meals means a larger spike in metabolism. Over the course of a day or week, given an equal amount of calories, the number of meals doesn’t seem to matter — it all evens out.
5. Protein causes bone, liver and kidney damage.
Some studies done on protein detected that protein consumption (especially from animal sources) was linked to increased urinary calcium, which was thought to lead to reduced bone mass over time. Later studies determined that urinary calcium was a poor measure for bone mass, and that protein actually had a protective effect or no effect on bone. Also, these studies did not take into account the increased calcium absorption that occurs via the gut when we ingest animal protein.
Early studies showed that high protein diets increased glomerular filtration rate (GFR), a marker for waste filtration in the kidneys. Some leapt to the conclusion that increased GFR was a sign that increased protein put too much stress on the kidneys.
Later research however, has shown that kidney damage does not occur as a result of a diet high in protein. While it may exacerbate already existing kidney issues, it does not CAUSE kidney damage. This is similar in regards to the liver. While high protein diets may exacerbate existing liver dysfunction leading to ammonia build up, it does not cause liver damage. A healthy liver can handle protein just fine.
6. Alkaline diets promote health and acidic diets promote disease.
There is this idea going around that the food we eat can effect the pH of our blood and extracellular fluid. An acidic state in the body leads to disease and a more alkaline state prevents disease. However, what we eat impacts the pH our urine, not the fluids in our body (i.e. blood).
Acidic foods are things such as animal products, dairy and grains. Alkalising foods are things like fruits and vegetables. What makes a food acidic or alkaline is determined by the chemical structure of nutrients in a particular food group and how it is metabolised in the body.
It has been thought that you could test the pH of the body through testing the urine. Depending on what you eat does have an effect on your urine pH, so if you have meat your urine is more likely to be acidic compared to having a green smoothie.
However, the pH of your urine has nothing to do with pH of your blood and body. The pH of blood and extracellular fluid is tightly regulated by the kidneys through various mechanisms. The pH of the blood will only change to an acidic pH in serious disease such as end stage kidney failure. The pH of our blood is tightly regulated between a neutral 7.35-7.45. Any variations in pH above or below these numbers can lead to coma and death. Therefore, what you eat has little effect on the pH of your blood as it is so tightly regulated. If your blood pH was to be affected by what you ate, you would not survive very long.
Despite all of this, certain foods we eat leave an acidic or alkaline “ash” after they are metabolized and this can be seen in the urine, which is why the pH of our urine changes depending on what we eat. So if you have a green smoothie for breakfast it is likely your urine would be an alkaline pH, as opposed to if you ate a steak, it is likely your urine pH would be acidic.
Don’t get caught up in hype driven headlines and sometimes the truth will go against your world view. At the end of the day, fear mongering, extremism, pseudo science and sensationalism is what sells, not science.
7. Whole wheat bread is better than white bread.
White bread (made from wheat flour) and whole-wheat bread both contain gluten and related proteins. They provide a similar number of calories, but whole-wheat bread has lower glycemic and insulin indices, and so its consumption results in a lower insulin release. For that reason, and because of its higher fiber and micronutrient content, whole-wheat bread is claimed to be healthier than white bread.
What the media frequently fails to mention is that the actual differences between white bread and whole-wheat bread are relatively small. Yes, whole-wheat bread has a higher fiber content — but this content pales compared to that of many fruits and vegetables. You most definitely don’t have to eat whole-wheat products to get enough fiber in your diet! And yes, white bread does lose more micronutrients during processing — but those micronutrients are often reintroduced later (the bread is then called “enriched”).
If anything, what makes whole-wheat bread markedly different is its higher phytic-acid content. Phytic acid binds to dietary minerals, such as iron and zinc, and can thus slightly reduce their absorption in the body. On the plus side, phytic acid has a protective and anti-inflammatory effect on the colon. So there’s a little bit of bad and a little bit of good.
Though whole-wheat bread is claimed to be far healthier than white bread, they aren’t that different, and neither contains high levels of fiber or micronutrients.
8. To lose fat, don’t eat before bed.
Some studies show a fat-loss advantage in early eaters, others in late eaters. Overall, early eaters seem to have a slight advantage — nothing impressive.
In real life, there are two main reasons why eating at night might hinder fat loss, and both are linked to an increase in our daily caloric intake. The first reason is the simplest: If, instead of going directly to bed, we first indulge in a snack, then the calories from that snack are calories we might have done without. The second reason is that, when we get tired, we tend to eat to keep going — with a predilection for snack foods or sugary treats. So if we stay awake at night, especially to work or study but even just to watch TV, we’re more likely to eat, not out of hunger, but to help fight sleepiness.
Eating late won’t make you fat, unless it drives you to eat more. It can also be harder to resist tasty, high-calorie snacks after a long day.
9. Cardio in a fasted state leads to greater weight loss
Let’s get one thing out of the way. If you exercise near maximal capacity (sprints, HIIT, heavy lifting …), eat first, or you’re more likely to underperform.
Most people who choose to work out in a fasted state, however, opt for some form of “cardio” (aerobic exercise), such as jogging. During cardio, performance and energy expenditure while fasted are about the same as in a fed state. In a fasted state, you’ll burn more body fat, but that won’t make it easier for you to use body fat as fuel during the rest of the day (when you’re fed).
You’ll also burn a tiny bit more muscle, but you’ll grow it back faster afterward, too, so that it seems to balance out (as long as you get enough protein). Finally, cardio suppresses appetite less on a fasted state than on a fed state, but that doesn’t translate into a significant difference in daily caloric intake.
There’s very little difference between cardio on a fed or fasted state with regard to fat loss, muscle preservation, daily caloric intake, or metabolic rate. What really matters, then, is you. Some people feel lighter and energized when they do cardio on an empty stomach, while others feel light-headed and sluggish. Fed or fasted state: pick whichever makes you feel better.
10. Breakfast is the most important meal of the day
“Breakfast is the most important meal of the day” is something we have all heard before from parents, health bloggers, doctors, and ad campaigns. But the health advantage of consuming a regular breakfast has been overhyped.
People who are #TeamBreakfast have pointed to observational studies showing a higher BMI in breakfast skippers. However, clinical trials have pointed to personal preference being a critical factor. Some people will subconsciously compensate for all the calories they skipped at breakfast, while others won’t feel cravings of the same magnitude. In one trial, women who didn’t habitually eat breakfast were made to consume it; they gained nearly 2 pounds over a 4-week period.
Individual responses do vary, so don’t try to force yourself into an eating pattern that doesn’t sit well with you or that you can’t sustain — it may end up backfiring.
Another popular claim is that skipping breakfast can crash your metabolism. But studies in both lean and overweight individuals have shown that skipping breakfast does not inherently slow your resting metabolic rate (RMR).
One area where the “don’t skip breakfast” mantra may hold true is in people with impaired glucose regulation. These individuals may want to play it safe and avoid skipping breakfast in order to achieve better day-to-day glucose management.
You don’t need to eat breakfast to be healthy or lose weight. You should base your breakfast consumption on your preferences and personal goals. Feel free to experiment to see if you want to make skipping breakfast a habit.
11. You must eat protein immediately after your workout.
When you exercise, you damage your muscles, which your body then needs to repair, often making them more resilient (bigger) in the process. The raw material for this repair is the protein you ingest, yet the existence of a post-workout “anabolic window” for this ingestion remains a contentious topic in the literature.
“You need protein right after your workout” may not be a myth so much as an exaggeration. Consuming 20-40g of protein within the two hours following your workout may be ideal, but it isn’t necessary. What matters most is your daily protein intake. To maximize muscle repairs, aim for 1.4–2.2 g of protein per kilogram of bodyweight per day (0.64–1.00 g/lb/day).You don’t need protein immediately after your workout, but you might benefit from 20–40 g within within the next couple of hours (and before bed). What matters most, however, is how much protein you get over the course of the day.
12. Clean Eating is a misconception.
People seldom agree on what “clean” actually means. For some, it means avoiding everything that isn’t natural. For others, it means eating all your food raw (raw and cooked food have their pros and cons in various instances – no absolutes) or avoiding all “risky foods” even at the cost of living on meal replacements and other supplements. One common point of clean diets is their negativity: They tell you what clean eating is by telling you what not to eat.
Veganism can be considered the prototypal clean diet, as it shuns all meat products both for ethical reasons and for better health. But although vegans and vegetarians do live longer, this may be influenced by reasons unrelated to food. For instance, people who stick to a vegetarian diet are more likely to also stick to an exercise regimen, practice relaxation exercises (meditation, yoga …), and neither drink in excess nor smoke.
In fact, compared to people eating a varied omnivorous diet, vegans (and, to a lesser extent, vegetarians) are more likely to get less than the optimal amount of some nutrients, such as vitamin B12. However, those nutrients can easily be supplemented — nowadays, there are even plant-based options for EPA, DHA, and vitamin D3.
In saying all of this, these days you can’t simply “eat your veggies” — you need to make sure they’re organic. This is presented as self-evident, on the principle that “natural” is good whereas “synthetic” is bad; yet research has so far failed to link organic foods, plants or animal, to better health. It doesn’t mean a link cannot exist, but the organic-versus-conventional debate is complex, and can change both with the foods under scrutiny and with the individuals eating them.
One misconception is that no synthetic substance can be used to grow organic crops, whereas the National List of Allowed and Prohibited Substances makes some exceptions. Another misconception is that no pesticide can be used to grow organic crops, whereas natural pesticides exist, are used to grow organic crops, and are not always better for the consumer or the environment.
Pesticide residues in food are a valid concern, though it should be noted that the vast majority of the food on the market contains residues below the tolerable limits set by government agencies. In addition, rinsing, peeling when possible, and cooking can reduce the amount of pesticide left on your food.
And if that is not enough, some “clean eating” gurus recommend that you only eat your food raw, so as not to “denature” its nutrients. As an absolute, this rule is bunk. Raw food, like cooked food, can have pros and cons, depending on the food and context.
It’s easy to see how one can push the “clean eating” obsession too far, even all the way into orthorexia. It doesn’t mean that all foods are equal, and you certainly should favour whole foods over processed foods — most of which are nutrient-poor, calorie-dense, and easy to overeat — but you shouldn’t fear that eating anything but raw organic veggies is going to drastically shorten your lifespan.
“Clean eating” is the new fad, but gurus don’t even agree on which foods are clean and which are not. Stick to the basics. Favour whole foods (but don’t feel like any amount of processed foods will kill you), eat organic if you want and can afford it, peal or wash your vegetables and fruits (especially those with higher levels of pesticide residue, such as strawberries), and avoid stressing too much about what you eat, since stress can shorten your lifespan.
13. Foods are better than supplements.
It’s been repeated so often that the word “natural” has a positive connotation whereas “synthetic” or “chemical” has a negative one.
The truth, of course, isn’t so clear-cut. Some compounds that are found in various food sources (plants and animal products) may be isolated and synthetically made into supplemental form for specific therapeutic uses, which have been studied in clinical trials. In doing so, they may be more effective in supplemental form because in food, they may be poorly absorbed or exist in small amounts, meaning a person would have to eat large amounts of a particular food to get the therapeutic dose.
One example is the curcumin in turmeric, which is a potent anti-inflammatory but very poorly absorbed. Therefore, it is often supplemented with piperine (a black pepper extract) or taken in liposomal form to increase its otherwise low dietary bioavailability.
The same goes for some vitamins. For instance, phylloquinone (K1) is tightly bound to membranes in plants and so is more bioavailable in supplemental form. Likewise, folic acid (supplemental B9) is more bioavailable than folate (B9 naturally present in foods), though that may not always be a good thing.
Many supplemental vitamins have natural and synthetic forms. This makes them accessible to more people. For example, if B12 could not be synthesized, it would be prohibitively expensive as well as unsuitable to vegans.
On the flip side however, some supplements are unnecessary due to a lack of good evidence for their efficacy in humans, an adequate amount of the supplemental nutrient is found in food and/or better absorbed via food, they may cause harm when isolated into a supplement due to a lack of food synergy, they may interact negatively with drug or they may have a low safety threshold.
You’ve likely heard all 13 of these myths repeated at one time or another — by a friend, on a blog, or somewhere in the media. Misinformation is rampant, difficult to identify, and unfortunately spreads much faster than facts.
And really, this is just the tip of the iceberg. You’ll see often see sensationalist headlines based on a study with unsurprising results.
This article and my last article hopefully removed unwarranted fear and misunderstanding around certain health and nutrition topics. When you are trying to be healthy, I know all the fear mongering and misinformation can be stressful and debilitating. It can also be expensive!
Just remember, good health requires consistent dedication to simple, healthy diet and lifestyle habits. Eat as much whole, minimally processed foods as you can (animal products and plants), pick a diet that works for you, drink water, get enough sleep, stress less, get enough exercise, spend time outdoors in the sun, spend less time on social media, form strong/functioning interpersonal relationships, work to have a positive mindset, indulge in moderate amounts of sugar once in a while, don’t smoke and consume modest amounts of alcohol.