The Case for Real Food
Walk to the edges of the grocery store, and you’ll find food that our ancestors would likely recognize: fresh food like apples, carrots, fish and eggs.
The rest of the grocery store is filled with food that our ancestors probably wouldn’t recognize: ultra-processed foods like chips and soda formulated in industrial laboratories. Researchers have linked ultra-processed food consumption to increased risk of mortality, heart disease, cancer, depression and more.
To avoid health risks, nutrition experts often recommend sticking to the perimeter of the grocery store and purchasing real food. But what exactly is real food?
Real food is food from nature in its whole, unprocessed state.
“Real food is anything that came out of the ground or from animals that ate anything that came out of the ground,” said Dr. Robert Lustig, professor of pediatric endocrinology at University of California, San Francisco (UCSF) and author of “Metabolical.”
On the plant side, real food includes vegetables, fruit, nuts, grains and legumes. On the animal side, it includes eggs, dairy, seafood and meat.
Sounds simple? That’s because it is. Until real food is processed by the food industry, it contains simple, single ingredients recognizable for what they are.
Of course, it’s not always so black and white. There are different levels of food processing, as outlined by Dr. Carlos Monteiro and colleagues in the Nova Food Classification System. Unprocessed and minimally processed foods lie at one end of the spectrum. They include fruits and vegetables, grains, eggs and meat — what we refer to as “real food.”
Ultra-processed foods lie at the other end of the spectrum. They are manufactured from large quantities of starches, sugars and oils combined with many additives to make the food more palatable. Ultra-processed foods include packaged snacks, sugary drinks, instant soups, frozen meals, mass-produced breads — and most of the other products lining today’s grocery store shelves. According to Monteiro and other experts, ultra-processed foods are the real problem.
Protect the Liver
Dr. Lustig boiled down his food philosophy to six words: “Protect the liver. Feed the gut.”
“Any food that does both is healthy. Any food that does neither is poison, and any food that does one or the other is somewhere in the middle,” he said.
Real food both protects the liver and feeds the gut; ultra-processed food does neither. But what does that mean? Let’s break it down a little further.
Real food protects the liver from the onslaught of refined starch and sugar in ultra-processed food. The overwhelmed liver has no choice but to convert the excess energy into fat, which impairs its functioning and eventually leads to insulin resistance and chronic metabolic diseases.
Metabolic diseases are related to abnormal metabolism, or burning of energy, in different areas of the body. They include Type II diabetes, cardiovascular disease, cancer, dementia, hypertension, lipid disorders, fatty liver disease and polycystic ovary syndrome (PCOS) — most of the lifestyle-related conditions slowly degrading the nation’s health.
Our “slow pandemic” of chronic disease has been rising for decades, driving up healthcare costs and disabilities, according to the Centers for Disease Control and Prevention (CDC). Sixty percent of Americans have one chronic disease, and 40 percent suffer from two or more.
How can we protect our liver and reduce our risk of chronic disease? Fiber plays a key role because it slows the absorption of sugar molecules.
“Fiber protects the liver by reducing the glucose and fructose absorption and thus reducing the tsunami hitting the liver,” Dr. Lustig said.
Fiber also slows the absorption of glucose into the bloodstream, preventing blood sugar highs and lows known as the “blood sugar roller coaster.” This roller coaster isn’t a fun ride, causing a slew of symptoms from mood swings to fatigue and cognitive impairment. Patients can be misdiagnosed for years, with doctors claiming the problem is “all in their head.” Really, the problem is in their diet.
“I’ve seen people diagnosed with conditions like bipolar disorder or attention deficit disorder who have these kinds of blood sugar patterns,” nutritional psychiatrist Dr. Ann Childers told me in an April 2020 interview for Medium. “Once the patterns resolve, they start feeling better.”
How can people resolve the blood sugar roller coaster? According to Dr. Childers, the answer is clear — avoid ultra-processed carbohydrates. In other words, eat real food.
Real food also contains an abundance of antioxidants and phytonutrients, beneficial compounds that safeguard our health. Colorful fruits and vegetables — like tomatoes, blueberries and beets — are especially rich in these protective properties.
“There are thousands of compounds in food, like all of these phytonutrients, that are powerful influences on health. You really can’t put everything in a vitamin and expect to be fine,” said Dr. Thomas Flass, pediatric gastroenterologist with Kalispell Regional Healthcare in Montana.
Feed the Gut
Real food also protects our gut microbiome and the 100 trillion bacteria that live there.
“When you’re pregnant, they say you are eating for two. Actually, all of us are always eating for 100 trillion,” Dr. Lustig said.
What do our gut bacteria eat? You guessed it — fiber. Real food is naturally packed with fiber, but fiber is stripped from ultra-processed food. That’s bad news for our gut microbes, which starve when we don’t feed them enough fiber.
“What happens if you don’t feed them? Dr. Lustig asked. “They eat you! They will eat the mucin layer right off of your intestinal epithelial cells.”
The mucin layer is a protective mucus coating that lines the gut wall. When the mucin layer degrades, it can lead to leaky gut, irritable bowel syndrome, inflammatory bowel disease, food allergies and more. In addition, Dr. Lustig notes that the same proteins that protect the gut, called zonulins, also protect the brain.
“You could end up with leaky brain to go along with your leaky gut, and that could precipitate depression, psychiatric disease and possibly dementia,” he said.
The gut-brain connection goes further still, with many researchers referring to the gut as the “second brain.” Altered gut bacteria, called dysbiosis, can affect everything from mood to brain development to risk of neurocognitive disorders.
“Ten years ago, it sounded like science fiction. Now, the top journals in the world are all publishing articles strengthening the association between gut health and brain health, up to and including Alzheimer’s, Parkinson’s and autism,” Dr. Flass said.
Dr. Flass emphasized the impact of nutrition on children, starting as early as conception and the womb. He said the first three years of life is a crucial window during which our bodies turn certain genes on and off based on environmental factors like nutrition. This process is called epigenetic programming, and it can affect health years down the line.
“These epigenetic changes may last with children for the rest of their lives, predisposing them to health or disease — everything from obesity to diabetes, future risk of heart disease and even future risk of cancer,” said Dr. Flass, who recently published a book on the topic called “Feeding Our Children.”
Slow Pandemic, Fast Pandemic
Real food may not only be the solution to our “slow pandemic” of chronic disease but perhaps can help with our “fast pandemic” of COVID as well. One way diet can help prevent severe COVID outcomes is by optimizing immune system function.
“You need a functional immune system in order to fight off any infection,” Dr. Flass said. “The way that most Americans are eating leads to suboptimal immune function.”
For instance, most Americans are consuming far too many Omega-6 fatty acids from ultra-processed foods and seed oils (such as canola oil). Meanwhile, they are consuming far too few Omega-3 fatty acids from real foods like fish and chia seeds. The skewed fatty acid ratio pushes our bodies toward a pro-inflammatory state, setting us up for COVID complications.
“The reason people end up in the hospital and die of COVID is not the virus — it’s the cytokine storm,” Dr. Lustig said. “It’s the immune system going haywire trying to clear the virus.”
Cytokines are inflammatory proteins released by the immune system. They are crucial for fighting infections, but they must remain in balance. If left unchecked, cytokines can lead to rampant inflammation that wreaks havoc on the body.
Again, fiber is essential here. Our gut microbes convert soluble fiber into short chain fatty acids that buffer the immune system response.
“People who don’t consume fiber are not getting those short chain fatty acids, and so their cytokine response ends up going way out of control,” Dr. Lustig said.
Chronic conditions like diabetes, heart disease and cancer also increase our chances of severe illness from COVID, according to the CDC.
“Our chronic disease is making our acute disease worse,” Dr. Lustig said.
Even if you haven’t yet been diagnosed with a chronic condition, it doesn’t mean you’re in the clear. Only 12 percent of Americans are metabolically healthy, according to researchers from University of North Carolina, Chapel Hill. That means 88 percent of Americans have suboptimal metabolic markers, including blood sugar, triglycerides, HDL cholesterol, blood pressure and waist circumference.
“Prevalence of metabolic health in American adults is alarmingly low, even in normal weight individuals,” the researchers conclude. “The large number of people not achieving optimal levels of risk factors, even in low-risk groups, has serious implications for public health.”
Before, these serious implications meant increased risk for chronic disease and all-cause mortality. Now, they also mean increased risk for severe illness and death from COVID.
Dr. Lustig describes multiple mechanisms at work here. For one, insulin increases the number of ACE2 receptors on our cells. These receptors regulate water balance, and COVID uses them to inject its RNA into the cell. The more ACE2 receptors we have, the greater chances for infectivity and severe illness. Glucose also crystallizes around the edges of the ACE2 receptors, holding them open so the virus has an easier time injecting its RNA.
“It’s been shown that people with higher blood glucose are much more susceptible and get much sicker with COVID,” Dr. Lustig said.
Thus, it’s imperative to keep insulin and glucose levels down during the pandemic (and after). The best way to do this is to eat real food, limiting the refined carbohydrates and sugars that come with ultra-processed food.
“Ultra-processed food is the worst thing you can eat with a virus like this,” Dr. Lustig said. “Unfortunately, ultra-processed food is what everyone is consuming because they’re stressed and looking for cheap food. That’s why all of the ice cream and pasta and macaroni and cheese are gone from the store.”
Dr. Lustig said that by eating ultra-processed foods, people are making it more likely they will succumb to COVID.
The Real Food Solution
We now know the importance of eating real food for COVID and chronic disease outcomes, as well as overall mental and physical health. But the question remains, how can we start making real changes in our lives?
Dr. Flass said the first step is to ditch the sugary drinks. These include soda, sports drinks, juice, flavored milk and sweetened coffee or tea. Healthier alternatives include water, unsweetened tea or coffee, plain milk — perhaps even sparkling water with lime. Dr. Flass said this shift alone can greatly enhance our health.
The next step is to scan the ingredient lists on household ultra-processed food products and ditch the ones with added sugars. Of course, cookies and ice cream are obvious culprits. But make sure to examine the less-obvious culprits as well, such as salad dressing, protein bars, yogurt, cereal and bread.
“If you start reading the labels, a lot of the popular food items have to go in the trash,” Dr. Flass said. In fact, about 74 percent of processed food products contain added sugars. These sugars are concealed in the marketplace by at least 300 different names, such as cane sugar, rice syrup, agave nectar and fructose.
The next step is to start cooking real food. “You can’t rely on someone else to cook your food and expect to be healthy,” Dr. Flass said.
Meals don’t have to be complicated. It’s possible to make quick, healthy dishes with relatively few ingredients.
For instance, Dr. Flass likes to throw chicken and vegetables in a pressure cooker and serve it on top of quinoa. “It’s satisfying, and it has a lot of fiber and phytonutrients,” he said.
He’s also found that roasted vegetables are a big hit with children. Parents can buy Costco-sized bags of frozen vegetables, drizzle them with olive oil and spices and throw them in the oven for 30–40 minutes.
“It’s super easy and comes out tasting good, while preserving a lot of nutrition,” he said. “Cooking is not as complicated as people think. You just have to get started.”
How are you going to start eating more real food? It could be as simple as grabbing an apple instead of a muffin or choosing water over soda. It could be sending your children to school with vegetable sticks instead of potato chips. It could be cooking a homemade meal instead of ordering takeout. It could be simply talking to your family about the benefits of eating real, whole foods.
Every little step toward real food matters.
As Dr. Flass says, you just have to get started.
