Sorry, Eating Entire Bag of Chips Still Not a Great Idea - On Nutrition (2024)

DEAR DR. BLONZ: I wonder if you could comment on a family discussion. My father-in-law often eats an entire bag of potato chips at one sitting -- a 10-ounce bag, not an individual 1-ounce bag. He says that his body can only absorb so many of the calories that he eats at once, and that the rest will just pass on through. In this way, he claims he will actually absorb fewer calories by eating the whole bag at once than if he ate just a portion every day until it was gone. Is this true? -- K.B., via email

DEAR K.B.: There is some logic to your father-in-law's position: namely, that in some circ*mstances, there can be inefficiencies in caloric absorption when the body is dealing with an uncharacteristic dietary overload. The backstory, however, can help complete the picture.

The human body is oriented for efficiency, avoiding any waste of calories and other resources whenever possible. Muscles, for example, require energy (calories) even while at rest. (Think of the analogy of gas consumption by an eight-cylinder car at idle versus a four-cylinder car.) Working muscles adapt to our activity routines, increasing their mass to meet the demands of habitual load. The converse is also true: Muscles shrink when decreased activity becomes the new norm.

Similar adjustments occur with digestion -- system-wide adaptations to what, when and how much we regularly eat. This helps explain why we tend to get hungry at our typical mealtimes and why we might be at greater risk for indigestion when eating at unusual times, such as after traveling through several time zones. This also explains why abrupt, radical shifts in the foods we eat might not "go down easy," even if the change is toward more healthful fare.

Does the above suggest that having a 10-ounce bag of chips -- the equivalent of 10 1-ounce servings -- at one sitting might be an acceptable strategy? Hardly. Downing that full bag will result in increased blood levels of the chips' food components -- approximately 90 grams of fat, 160 grams of carbohydrate and 1,500 mg of sodium. All of that will be waiting in the queue for absorption, and it is complemented by few, if any, healthful assets.

Fat, carbs and sodium are not the snack-food elements you want to accentuate, even if absorption isn't happening with 100% efficiency. What fails to be absorbed ends up traveling the rest of the way through the intestines, bringing nutrients to areas where they're not often seen. This can result in indigestion, gas and other negative effects. And if the bag of chips is consumed within a couple of hours of another meal, the digestive and absorption machinery will already be up and running -- robbing the assumption of caloric wastage of its heft.

A sizable load of fat, carbohydrates and sodium, from a processed food with few healthful assets, increases elements associated with many chronic diseases. So even if you feel you can defend the action using a caloric-inefficiency rationale, health logic argues that you are not doing yourself any favors.

Send questions to: "On Nutrition," Ed Blonz, c/o Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to [email protected]. Due to the volume of mail, personal replies cannot be provided.

DEAR DR. BLONZ: I was reading about the acid-base balance in the body and was surprised to learn that the pH of lemon juice is lower than that of vinegar, which means it's higher in acid. This makes me wonder how I can tolerate drinking lemon juice straight, but lower-acid vinegar takes my breath away. Does pH not equal the acidity we perceive with our tastebuds? I had always thought that if I substituted lemon juice for vinegar in a dressing or recipe, I needed to use slightly more because it has less acid. -- G.G., San Diego, California

DEAR G.G.: Degrees of acidity or alkalinity (acid or base) are expressed in terms of a measure known as pH, which is based on the concentration of free hydrogen ions. pH ranges from 0 to 14, with 7.0 being neutral. Distilled water has a pH of 7.0. If the pH is above 7.0, the substance is a base; if it is lower, it's an acid.

The greater the numerical distance from 7.0, the stronger the acid or base. Also, pH is a logarithmic scale, where every integer change represents a tenfold difference in acidity or alkalinity, so a substance with a pH of 1 will be 10 times stronger than an acid with a pH of 2. A typical cup of coffee has a pH of 5.0; compare this to the acid in our stomach, with a pH between 1.5 and 3.5, or battery acid, with a pH of 0.8.

In the body, the physical act of digestion begins the moment food enters the mouth, where it is acted upon by mechanical mixing with saliva and its enzymes, then with acids in the stomach, then digestive juices with their enzymes in the intestines. The process is to break complex foods into parts suitable for absorption. A food's pH can change after being metabolized (broken down), so lemons, while more acidic before the swallow, actually have an alkalizing effect on the overall metabolism after digestion and absorption.

The pH of a healthy human body is slightly alkaline and within a very narrow range, between 7.35 and 7.45. Chemical reactions in the body rely on specific pH levels, so overlapping systems are designed to maintain the correct pH to make things happen as needed. Different pH levels are used in areas responsible for particular types of processing during digestion. For more on the pH in different body parts, see b.link/a6ev7x5s.

Now, for the specifics of your question: pH does not necessarily correlate with smell or taste. The vinegar used in foods comes from acetic acid, a substance that is produced when foods decompose. The association with spoilage explains why a sniff of vinegar is such an unpleasant experience for many. Our senses are designed to assess things close to the body, especially anything being considered for ingestion. Vinegar's scent can trigger caution designed to keep us away from risks; for some, the smell of vinegar is so unpleasant that it can cause nausea.

Contrast that with a lemon scent, which is not associated with anything negative. Indeed, the pleasantness of the lemon scent makes it a popular fragrance additive, especially to household products.

Send questions to: "On Nutrition," Ed Blonz, c/o Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to [email protected]. Due to the volume of mail, personal replies cannot be provided.

DEAR DR. BLONZ: I would appreciate advice on improving the diet of my three young girls. I run up against refusals and "not hungrys," which later become pleas for their "regular." Special considerations given to one child are noted and questioned by the others. -- O.Q., Hayward, California

DEAR O.Q.: It is common for parents to be concerned when their children choose "junk foods" over healthier foods. The example set by the adult family members is key. Parents should refrain from the "do what I say" model and demonstrate healthful eating behaviors instead. Healthful eating benefits you, but also plants the seeds of these behaviors in your children, which can blossom later.

Consider what might be going through your child's mind as they sit down at the table and are told, "This is what you're eating." There are strategies that can help you lessen the surprise while stimulating your child's appreciation for nutritious food and feel more in command. The key areas are a consistent availability of healthful foods, menu planning, meal preparation and coping with unpredictable mealtime behavior. If there is more than one child, they can take turns being the primary "adviser" while agreeing to respect each other's choices.

When possible, take the kids grocery shopping -- but don't shop on empty stomachs, and make sure responsibilities have been established. Have them select their favorite fruits and vegetables, which can increase the chances they'll eat them at mealtime. At home, establish ways they can help with meal preparation -- being involved removes the mystery and can increase satisfaction with foods.

Associate healthful eating with your kids' physical development, including their skin and hair, appealing to the fact that they are making decisions about their bodies that will last their lifetime. Coercion or the promise of rewards can label a food as something not worth considering on its own merits.

Occasionally missing a meal or failing to eat from all the food groups are not signs of impending malnutrition. Avoid custom-cooking if the meal offered is rejected. Have some bread or fruit on the table for kids to pick at while they watch others enjoy the rest of the meal.

The senses of smell and taste can develop out of sync, taking mealtime behaviors with them. While there is no way to predict an individual's road to physical maturity, know that things change as they develop; food fixations and phobias are a fact of life that tend to go away with time.

Nobody knows your children and their habits better than you do. However, speaking with other parents to learn what their children enjoy can provide additional information on factors that influence eating choices.

There are resources available -- thenourishedchild.com has a blog and podcast. Consider a garden at home or in a community plot, and encourage your children's school to establish a student garden. Caring for plants and following food from seed to plate is an enriching, enlightening experience for young minds.

Send questions to: "On Nutrition," Ed Blonz, c/o Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to [email protected]. Due to the volume of mail, personal replies cannot be provided.