Today’s blog is a follow-up to “Incorrect Nutrition Facts Labels Part 1” published earlier this year.
Nutrition science is a dynamic field and we are constantly learning and discovering new things. As a dietitian, it is my job to stay current with the latest evidence and base my practice on it. Over time our understanding evolves and what we once believed to be true may no longer be true.
Beyond the changing research, there’s also the issue of social media influencers presenting opinions as fact. Just because someone has a large following or sounds like an authority doesn’t mean what they’re saying is true. Tip: Podcasts are the latest medium for spreading nutrition myths.
“Fact”: White rice is bad for you
Even though rice is a cultural staple for people all over the world, we have been told for years to avoid “white foods,” including white rice. I’m embarrassed to admit that when I first started working as a nutritionist, I also told people to avoid white rice.
Although brown rice has some nutritional advantages over white rice (it has slightly more fiber and minerals like magnesium), many of the negative opinions about white rice are deeply rooted in the fact that Western culture tends to use its idea of ”healthy food” as the gold standard, which historically has been brown rice, mixed vegetables, and fish or chicken breast.
While this may work for some, it is not representative of the diversity of our population.
There are many ways to eat healthily and our cultural foods should be part of it.
Food, culture and identity are deeply rooted and calling a cultural staple “unhealthy” is an act of disrespect to that culture and is wrong in so many ways. People should be able to eat and enjoy the foods they grew up with without being made to feel like they’re “bad” or “wrong.”
From a practical standpoint, white rice cooks much faster than brown rice, the rice itself is great for carrying veggies and protein, and it’s cheap and can be prepared in advance.
Fact: You don’t need carbohydrates to live
Carbohydrates have long gotten a bad rap, and the idea that you don’t need carbs is a common nutrition myth spread primarily by adherents of low-carb and carnivore diets, especially on social media. People who follow these diets often claim that avoiding carbs has improved their health, caused them to lose weight, cleared their skin, and increased their energy. I’ve written about the carnivore diet here.
Although you can technically live without carbohydrates, that doesn’t mean it’s a good thing. Ideally, we’re trying to optimize our health, not just survive.
Our brains rely on glucose as their primary source of energy, and although our bodies can make glucose from other substrates in a process called gluconeogenesis, this is not as efficient a process as making glucose from simply carbohydrates.
Again, just because you can doesn’t mean you should.
There’s nothing wrong with a low-carb diet, but being afraid of carbs and severely restricting or completely avoiding them isn’t going to improve your physical or mental health. I’d also like to add that fiber is a carbohydrate, and anyone who claims fiber is unnecessary or harmful is not someone you should be getting nutrition information from.
Fruits, vegetables, whole grains, beans and legumes are all nutritious sources of carbohydrates that contain dietary fiber, which is important for gut health, helps maintain healthy cholesterol levels and stabilizes blood sugar levels in people with diabetes. Research shows that the healthiest diets are those high in plants.
Conversely, there is no research that proves that avoiding plants or severely limiting carbohydrates promotes health. There are always exceptions, but generally, the majority of us benefit from including carbohydrates in our diet.
Carbohydrate quality is also important: while refined carbohydrates play an important role in your diet, the majority of your carbohydrate intake should come from whole or minimally processed foods.
Fact: Saturated fats not linked to heart disease
Since the 1970s, the guideline has been to reduce saturated fat intake to reduce the risk of cardiovascular disease, but advances in science have shown that some foods high in saturated fat do not have a negative effect on heart health. However, it is not true that saturated fat is not linked to heart disease.
Saturated fats are found in a variety of foods. Most of them come from animals, such as meat, poultry, and dairy products, but tropical fats, such as coconut oil and palm oil, also contain saturated fats. It’s important to understand that all fats contain varying amounts of a mixture of saturated and unsaturated fats.
Read my post on seed oils here.
Current guidelines say less than 10% of your daily calories should come from saturated fats. If there was evidence showing that saturated fats were not linked to heart disease, this guideline would already have been adjusted.
Dairy is a popular food group studied in relation to saturated fat and heart health, and cheese has been shown to have a positive effect on blood fats compared to butter (which is only about 63% saturated fat).
In a recent systematic review and meta-analysis, researchers found that dairy fat ingested in the form of cheese reduces fasting circulating total cholesterol, LDL, and HDL compared to butter. This is not surprising, considering that butter is a completely different food from cheese. Cheese is a fermented food and contains protein, calcium, and many additional nutrients not found in butter, which is essentially pure fat.
Further studies are needed to confirm these findings, and there may also be differences between different types of cheese, such as hard and semi-soft cheeses.
Another recent area of research has been the examination of fatty acid chain length. Fatty acids can be classified as short, medium, or long chain. Short chain fatty acids are mostly produced in the large intestine as a by-product of fiber fermentation. Medium chain fatty acids are found in palm kernel, coconut oil, and dairy products. Long chain fatty acids are found in dairy products, beef, palm oil, and lard.
A systematic review found that long-chain fatty acids increase the risk of heart disease, while short- and medium-chain fatty acids are neutral. However, because most foods contain many different types of fatty acids, it is difficult to draw any conclusions.
When considering reducing saturated fats to improve heart health, what you replace them with is also important. It is generally accepted that replacing saturated fats with polyunsaturated fats is beneficial for heart health. These fats are found in fatty fish such as salmon and sardines, nuts and seeds, tofu, and soy. Vegetable oils such as canola are also high in polyunsaturated fats.
Research shows that replacing saturated fats with refined carbohydrates can have a negative impact on heart health.
Fact: Calcium supplements are necessary for bone health
Taking a supplement to get the mineral you don’t get enough of through your diet may seem like a logical choice, but research suggests there are some things to be careful of when it comes to calcium in supplement form.
There has been a lot of research on calcium supplements and bone health over the years, but the results have been mixed, so there is little scientific consensus.
Most of these studies have been conducted in postmenopausal women, a time when declining estrogen levels tend to accelerate age-related bone loss.
Information from the Women’s Health Initiative (WHI) study suggests that a combination of calcium and vitamin D is associated with a small improvement in bone mineral density but not fracture risk in postmenopausal women.
The United States Preventive Services Task Force (USPSTF) has similar findings, and neither organization recommends daily calcium supplements for fracture prevention in postmenopausal women.
Calcium supplements carry some risks. This 2021 meta-analysis looked at the relationship between calcium supplements and heart health. It found that calcium supplements appear to increase the risk of cardiovascular disease and coronary heart disease, but not cerebrovascular disease.
Age-related bone loss is a major concern, especially for women. Recommend lifestyle choices that support bone health, such as eating calcium-rich foods, weight-bearing exercise such as walking and strength training, and not smoking. Get a baseline bone density scan and follow up as recommended.
Fact: Everyone should eat a low-sodium diet
Sodium is an essential nutrient that regulates body fluids and maintains the normal functioning of muscles and nerves.
Blood pressure guidelines and some medical professionals have historically recommended a low-sodium diet (defined as less than 2300 mg sodium, or about 1 teaspoon of salt) based on the idea that a low-sodium diet would lower blood pressure and reduce cardiovascular events.
However, these recommendations have recently been called into question due to the lack of solid evidence to support such low intakes. The average sodium intake worldwide is 2.3-4.6g per day (1-2 teaspoons of salt), and some researchers claim that this amount does not increase the risk of cardiovascular disease. However, with sodium intakes above 5g per day, the risk increases.
Additionally, there is no research to suggest that a low sodium intake (within current recommendations) compared to the average intake translates to a lower risk of cardiovascular disease or death, and may even lead to an increased risk.
Graph source: Sodium and health: another challenge to current dogma | European Heart Journal | Oxford Academic (oup.com)
The PURE study, which followed 102,000 people for nine years, found that a moderate sodium intake (3-5g per day) is optimal for health, and that both low and high intakes were associated with increased risk of mortality and cardiovascular disease.
It’s hard to pinpoint just one nutrient in research. Sodium’s effects are even harder to pinpoint because they’re also affected by potassium intake. But most healthy people don’t need to worry about consuming too much sodium, so long as they focus on eating a variety of whole foods and avoiding highly processed foods.
Nutrition research is evolving, so we must always question our beliefs and embrace any developments. Make sure you get your information from trusted sources.
There are many people out there who will pass off their opinions as nutrition facts, so be skeptical of any story that seems too far-fetched or too good to be true — and it probably is.
