Common myths about diet, supplements, antioxidants and alcohol

Food myths
Reducing or eliminating fried foods, sugar and alcohol have been shown to help prevent diseases such as heart disease or cancer.

It’s pretty much an established fact that eating a healthy, well-balanced diet in sensible portions—in addition to other lifestyle habits—helps provide a panoply of benefits to both physical and mental health. Reducing excess body weight, and sugar and alcohol intake, for example, may help prevent heart disease. A healthy diet may also help reduce the risk of cancer.

Generally speaking, a healthy diet doesn’t mean you have to eliminate some foods completely, says Carolyn Lammersfeld, MBA, MS, RD, CSO, LD, Vice President of Integrative Care Services at Cancer Treatment Centers of America® (CTCA).

“The current dietary guidelines from the American Institute for Cancer Research are to reduce red meat and processed meats, primarily because of the association with colon cancer risk,” Lammersfeld says. “Eating more of a plant-based diet with whole grains, fruits and veggies, lean proteins and some fish makes sense for all people, but particularly for people with cancer. It’s helpful for heart health and to try to reduce the risk of a secondary cancer.”

The American public is constantly bombarded with nutritional do’s and don’ts. Eat this, not that. Lammersfeld cautions cancer patients, in particular, to do their homework about nutritional myths like the ones busted below.

Myth: Juicing is a good way to get more fruits and vegetables in your diet.

The juicing craze has been around for some time, and new, high-tech blenders allowing for virtually anything to be ground to a liquid have given it a boost. Juicing may be a good way to incorporate fruits and vegetables into your diet, especially if you otherwise may not consume them, but Lammersfeld says it’s important to be mindful of portion size.

“If you think about how many carrots would go into a 4-ounce glass of carrot juice, it can be significantly more than you’d typically eat,” she explains. “This may provide more carbs, which break down to simple sugar and may cause blood sugar to rise and fall rapidly. All that sugar enters the bloodstream, and then the pancreas has to secrete insulin so the sugar can enter your cells. Eating a lot of simple sugar at one time can raise insulin levels quickly. High insulin levels may lead to a rapid decline in blood sugar levels and leave you feeling tired. It’s preferable to eat whole fruits and/or vegetables.”

Standard blenders are typically incapable of grinding/pulverizing the most fibrous parts of fruits and vegetables—the skin and core. Since whole fruits and veggies (as opposed to just the juice) contain the highest amount of nutrients, it’s preferable to use a blender or juicer that blends all the edible parts of the produce instead of simply squeezing juice.

So, while juicing may help increase your consumption of fruits and vegetables, eating them is really better.

Myth: Sugar substitutes are better for you than sugar.

If you’re overweight and/or diabetic, artificial sweeteners may be a necessity if you want baked goods, desserts, soft drinks or other typically sugary foods and beverages. However, certain sugar substitutes—sucralose, saccharin, aspartame and others—found in many products are a source of controversy among health practitioners.

Research has suggested artificial sweeteners may cause an increased risk of weight gain and type 2 diabetes. Lammersfeld recommends using a natural sweetener such as Stevia over highly processed ones like sucralose and aspartame. Federal dietary guidelines suggest limiting added sugars to no more than 10 percent of daily caloric intake, which for a 2,000-calorie per day diet amounts to 50 grams. “Read the labels to help you monitor your intake,” she urges.

Myth: A gluten-free diet is good for you.

One of the more vogue trends of the moment is the gluten-free diet. Glutens are proteins in grains that help foods maintain their shape, sort of like glue. If you have a gluten sensitivity or intolerance, such as those caused by Celiac disease, gluten should be avoided.

Otherwise, Lammersfeld says there’s no evidence to suggest that gluten is bad for you. In fact, people who avoid gluten despite not having Celiac disease or another gluten sensitivity may experience nutritional deficiencies, according to a 2018 article published in the peer-reviewed medical journal, Gastroenterology & Hepatology.

Myth: Supplements are a good substitute for a poor diet.

A multivitamin may not make up for a poor diet, but it may have some benefit. Multivitamins may help you get your daily requirements of some nutrients that are difficult to get from food, such as vitamin D.

Regardless of how innocuous a protein powder, vitamin or supplement may seem, though, Lammersfeld says it’s imperative for anyone undergoing cancer treatment, or in recovery, to talk with their care team about what they’re taking. “It’s often unnecessary and may conflict with treatment,” she says. “It may seem benign, but it might matter."

Myth: Antioxidants can help fight cancer.

Molecules that may help neutralize free radicals (unstable molecules or atoms that may damage cells) are called antioxidants. The human body has mechanisms in place to fight free radicals, which are linked to cancer and other diseases. Fruits, vegetables and other plant-based foods—especially the most colorful fruits and veggies—contain antioxidants.

Fruits and vegetables are generally not restricted during cancer treatment, unless there are other considerations for a bowel obstruction, for example, so they can be a good source of antioxidants.

But do antioxidants help prevent or fight cancer? A review of several studies by the National Cancer Institute (NCI) “did not provide evidence that dietary antioxidant supplements are beneficial in primary cancer prevention.” In fact, the NCI recommends that antioxidant supplements be “used with caution.” Lammersfeld recommends patients always discuss questions or concerns about diet and supplements with their care team before adding or removing anything from their diet.

Myth: All fats are harmful.

There’s a widely held belief that all fat is bad. Not true. In fact, Lammersfeld says, the body absorbs vitamins A, D, E and K better with a little fat. Omega 3 fatty acids, which many Americans don’t consume enough of, may help cancer patients keep weight on during treatment, she says, in addition to being good for the heart.

“The key is to eat more monounsaturated and polyunsaturated fats found in avocado, olive oil, canola oil, nuts, seeds and fatty fish like salmon and tuna,” she says.

Myth: Alcohol, in moderation, is good for you.

Alcohol consumption is the subject of much debate, especially when it comes to imbibing during cancer treatment. While studies have suggested that moderate amounts of alcohol may reduce the risk of stroke or heart attack, too much alcohol may increase your risk of cancer and other diseases.

This year, the American Cancer Society (ACS) updated its guidelines on alcohol use, advising Americans not to drink any alcohol, but adding, “if you do, women should have no more than 1 drink per day and men should have no more than 2. A drink is 12 ounces of regular beer, 5 ounces of wine, or 1.5 ounces of 80-proof distilled spirits.”

The ACS cites alcohol use as “one of the most important preventable risk factors for cancer, along with tobacco use and excess body weight,” noting that alcohol use accounts for some 6 percent of all cancers and 4 percent of all U.S. cancer deaths.

According to the ACS, the following cancers have been linked to alcohol use:

The ACS says that “alcohol probably also increases the risk of cancer of the stomach, and might affect the risk of some other cancers as well.”

The U.S. Centers for Disease Control & Prevention concurs, saying, “For some conditions, such as certain types of cancer (e.g., breast cancer) and liver disease, there is no known safe level of alcohol consumption.”

According to breastcancer.org, research has consistently demonstrated that drinking any type of alcohol increases a woman's risk for hormone-receptor-positive breast cancer. “Alcohol can increase levels of estrogen and other hormones associated with hormone-receptor-positive breast cancer. Alcohol also may increase breast cancer risk by damaging DNA in cells,” the site says.

“Women who have three alcoholic drinks per week have a 15 percent higher risk of breast cancer” compared to non-drinkers, according to the nonprofit. “Experts estimate that the risk of breast cancer goes up another 10 percent  for each additional drink women regularly have each day.”

Lammersfeld says alcohol use is strongly discouraged during cancer treatment, and patients should talk with their doctors about having alcohol.

“Alcohol may interact with some cancer treatments, and could potentially increase the risk of side effects ,” she says. And if you’re overweight, it’s extra calories, and we know obesity increases the risk of many cancers, so consuming alcohol and sugary drinks doesn’t help. Even drinking very small amounts can have a big impact.”

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