Certain genes may mean that vegetables taste more bitter for some people.
The “taste gene” can affect how people perceive different flavors.
Taste bud sensitivity decreases as we age, so even your most disliked vegetables could become palatable later in life.
Why is it difficult for some people to eat vegetables?
Researchers at the University of Kentucky believe a certain gene makes compounds in some vegetables taste particularly bitter to some people, so they avoid nutritious, heart-healthy vegetables like broccoli, Brussels sprouts, and cabbage.
Such individuals may also have a similar sensitivity to dark chocolate, coffee, and beer, according to Jennifer L. Smith, a licensed registered nurse and postdoctoral fellow at the University of Kentucky School of Medicine and one of the authors of the preliminary study.
The study, which will be presented at the American Heart Association’s Scientific Sessions in Philadelphia November 16–18, is based on some previous work that found that this genotype was associated with the types of vegetables eaten by college students.
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The ‘taste gene’
Humans are born with two copies of a taste gene called TAS2R38. Those who inherit two copies of the variant called AVI are not sensitive to the bitterness of these chemicals. But those who inherit one copy of AVI and one copy of PAV are especially sensitive and find these foods particularly bitter, Smith said.
For this study, researchers investigated the possibility that this association existed in people with two or more cardiovascular disease risk factors. Over a 3-year period, they conducted a secondary analysis of data using a sample from a previous study that investigated gene interactions in people at risk for cardiovascular disease. They analyzed food frequency questionnaires from 175 people.
The average age of the respondents was 52. More than 70 percent of them were female. They found that people with the PAV form of the gene were more than 2 1/2 times as likely to rank in the bottom half of vegetables consumed.
This study could change how doctors approach people who are advised to change their diet in order to have a healthier cardiovascular system.
“This association could influence their ability to alter their diets to meet a heart-healthy eating pattern,” Smith said.
Still, Smith said more research needs to be done about the best way to encourage people to eat their vegetables.
“We hope to explore avenues that people with this gene can take to make food more palatable to them,” she said. “Down the road we hope we can use genetic information to figure out which vegetables people may be better able to accept and to find out which spices appeal to supertasters (those with heightened sensitivity to taste) so we can make it easier for them to eat more vegetables.”
Don’t always follow your gut
Tonia Reinhard, a senior lecturer at Wayne State University in Detroit and course director for clinical nutrition at the university’s school of medicine, said it’s intriguing that the University of Kentucky researchers identified genetic regions that relate to taste that can influence one’s food choices and potentially influence development of certain chronic diseases.
“Since fruits and vegetables contain numerous phytonutrients and essential nutrients that can reduce inflammation and oxidative damage — two key damaging processes linked to cardiovascular disease, cancer, diabetes, and other chronic diseases — anything that affects dietary intake of these foods can possibly influence disease development,” said Reinhard, a fellow of the Academy of Nutrition and Dietetics and past president of the Michigan Academy of Nutrition and Dietetics.
She added that people should remember that human taste perception is a complex process that is affected by numerous variables.
“It is useful for individuals to try to understand their own preferences and when unhealthful, use their cognitive function to override some of those,” she said.
Annie Mahon, a registered dietitian, nutritionist, and visiting lecturer in the department of kinesiology at Indiana University-Purdue University Indianapolis, called the study of genes that influence taste preferences an active area of research. She echoed concerns about the health implications of forgoing cruciferous, heart-healthy vegetables such as broccoli and cauliflower.
“These vegetables are good sources of fiber, folate, as well as vitamin C and K,” Mahon said. “These nutrients are important to maintain a healthy digestive and immune system, as well as heart health.”
She said options for individuals with this genotype could include cooking the vegetables.
“That may reduce the bitterness and therefore be found to have an acceptable taste,” she said. “Or individuals have to find other sources of those nutrients which should be fairly easy to do since there are lots of other options.”
Mahon said it is also important to remember that taste buds decrease in sensitivity as we get older.
“So just because you didn’t like a fruit or vegetable when you were young doesn’t mean you won’t like it as you get older,” she said.
However, most of them will make you hungry and unsatisfied.
If you don’t have iron willpower, then hunger will cause you to give up on these plans quickly.
The plan outlined here will:
Reduce your appetite significantly.
Make you lose weight quickly, without hunger.
Improve your metabolic health at the same time.
Here is a simple 3-step plan to lose weight fast.
1. Cut Back on Sugars and Starches
The most important part is to cut back on sugars and starches (carbs).
When you do that, your hunger levels go down and you end up eating much fewer calories (1Trusted Source).
Now instead of burning carbs for energy, your body starts feeding off of stored fat.
Another benefit of cutting carbs is that it lowers insulin levels, causing your kidneys to shed excess sodium and water out of your body. This reduces bloat and unnecessary water weight (2, 3Trusted Source).
It is not uncommon to lose up to 10 pounds (sometimes more) in the first week of eating this way, both body fat and water weight.
This is a graph from a study comparing low-carb and low-fat diets in overweight or obese women (4Trusted Source).
The low-carb group is eating until fullness, while the low-fat group is calorie-restricted and hungry.
Cut the carbs and you will start to eat fewer calories automatically and without hunger (5).
Put simply, cutting carbs puts fat loss on autopilot.
SUMMARYRemoving sugars and starches (carbs) from your diet will reduce your appetite, lower your insulin levels and make you lose weight without hunger.
2. Eat Protein, Fat and Vegetables
Each one of your meals should include a protein source, a fat source and low-carb vegetables.
Constructing your meals in this way will automatically bring your carb intake into the recommended range of 20–50 grams per day.
High-protein diets can also reduce cravings and obsessive thoughts about food by 60%, reduce the desire for late-night snacking by half, and make you so full that you automatically eat 441 fewer calories per day — just by adding protein to your diet (9Trusted Source, 10Trusted Source).
This study assessed the change in calorie intake and average body weight from 1970 to 2000. The average child now weighs 9 lbs (4 kgs) more than in 1970, while the average adult weighs about 19 lbs (8.6 kgs) more (5Trusted Source).
When comparing the change in average weight, the calculations equated almost exactly to the increased calorie intake (5Trusted Source).
The study showed that children now consume an additional 350 calories per day, while adults consume an additional 500 calories per day.
The debate about the cause of weight gain and the obesity epidemic is still debated. Some blame carbs, while others blame fat.
Interestingly, data from the National Health and Nutrition Examination Survey suggests that the percentage of calories from carbs, protein and fat has stayed relatively constant over the years (10Trusted Source).
As a percentage of calories, carb intake has increased slightly while fat intake has gone down. However, the total intake of all three macronutrients has gone up.
4. Weight Loss on Low-Fat and High-Fat Diets is the Same
This creates what is known as an “energy gap,” or a difference between calories consumed and calories burned.
Interestingly, research shows that obese people are significantly less physically active than those who are lean.
This doesn’t just apply to formal exercise, but also non-exercise activity such as standing. One study found that lean people stood for about 152 minutes longer each day than people with obesity (17Trusted Source).
The researchers concluded that if those with obesity were to match the lean group’s activity levels, they could burn an additional 350 calories per day.
If you’re confused about whether calorie counting is effective or not, then you’re definitely not alone.
Some insist that counting calories is useful because they believe losing weight boils down to the concept of calories in versus calories out.
Others believe that calorie counting is outdated, doesn’t work and often leaves people heavier than when they started. Both sides claim their ideas are supported by science, which only makes matters more confusing.
This article takes a critical look at the evidence to determine whether counting calories works.
What is a calorie?
A calorie is defined as the amount of heat energy needed to raise the temperature of one gram of water by 1°C.
Calories are normally used to describe the amount of energy your body gets from what you eat and drink.
Calories can also be used to describe the amount of energy your body needs to perform physical tasks including:
maintaining your heartbeat
The amount of energy provided by foods is normally recorded in thousands of calories, or kilocalories (kcal).
For instance, one carrot generally provides you with 25,000 calories, or 25 kcal. On the other hand, running on the treadmill for 30 minutes generally requires you to use 300,000 calories, or 300 kcal.
However, because “kilocalories” is an awkward word to use, people often use the term “calories” instead.
For the purposes of this article, the common term “calorie” will be used to describe kilocalories (kcal).
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How does your body use calories?
If you’re wondering why calories matter, here’s a quick overview of how your body uses them.
It begins with what you eat. Food is where your body gets the calories it needs to function.
During digestion, your body breaks down the foods you eat into smaller units.
These subunits can either be used to build your own tissues or to provide your body with the energy it needs to meet its immediate needs.
The amount of energy your body gets from the subunits depends on where they come from:
Carbs: 4 calories per gram
Protein: 4 calories per gram
Fat: 9 calories per gram
Alcohol: 7 calories per gram
Your body uses the calories produced from metabolizing these nutrients to power three main processes, which are listed below (1Trusted Source, 2Trusted Source).
Your body will use most calories to perform basic functions, such as providing energy to your:
The amount of energy required to support these functions is referred to as your basal metabolic rate (BMR). It makes up the largest proportion of your total daily energy requirements (1Trusted Source).
Your body will use part of the calories you consume to help you digest and metabolize the foods you eat.
This is known as the thermic effect of food (TEF) and varies based on the foods you eat. For instance, protein requires slightly more energy to be digested, whereas fat requires the least (3Trusted Source).
About 10–15% of the calories you get from a meal will be used to support the TEF (3Trusted Source).
5. Physical activity
The remainder of the calories you get from foods fuel your physical activity.
This includes both your everyday tasks and your workouts. Therefore, the total number of calories needed to cover this category can vary from day to day and person to person.
You need a calorie deficit to lose weight
Once your body’s immediate energy needs are met, any excess energy is stored for future use.
Some of it is stored as glycogen in your muscles, but most will be stored as fat.
It’s important to make the distinction between quantity and quality. Even foods that have the same quantity of calories can be of different nutritional quality and can have very different effects on your health (19Trusted Source, 20Trusted Source, 21Trusted Source).
2. Studies often measure weight loss rather than fat loss
Many studies only report the total amount of weight lost, without specifying whether this weight came from loss of fat, muscle or water.
Low-carb diets are known to reduce the body’s carb stores. Since carbs are normally stored together with water in your cells, lowering your body’s carb stores inevitably leads to water weight loss (39Trusted Source).
This may make it appear as though low-carb diets help participants lose fat more quickly than they do.
1. Studies controlling for these three factors put the myth to rest
To truly settle the debate on whether calories matter for weight loss, look at evidence solely from studies that control for the above three factors.
A recent review reports that weight loss programs incorporating calorie counting led participants to lose around 7 pounds (3.3 kg) more than those that didn’t. It seems that the more consistently you do the recording, the better (46Trusted Source, 47, 48Trusted Source, 49Trusted Source).
For instance, one study reports that participants who monitored everything they ate for 12 weeks lost twice as much weight as those who monitored less frequently.
In comparison, those who didn’t monitor at all actually gained weight (47).
There are three reasons why calorie counting works:
Tracking your calories can help you identify which eating patterns you need to modify to successfully lose weight (50Trusted Source).
Despite its lack of precision, tracking what you eat can give you an approximate baseline to work from and compare to when you’re trying to reduce the total number of calories you eat per day.
Finally, keeping track of what you eat can help you monitor your behavior. This may help keep you accountable for the daily choices you make and motivate you to continue progressing toward your goals.
You can somewhat counteract your natural tendency to inaccurately estimate how many calories you eat by using scales and measuring cups. These can help you measure food portions more accurately.
You might also want to try using the following visual guidelines to estimate your portion sizes. They’re less accurate, but useful if you have limited access to a scale or measuring cups:
1 cup: a baseball or your closed fist
4 ounces (120 grams): a checkbook, or the size and thickness of your hand, including the fingers
3 ounces (90 grams): a deck of cards or the size and thickness of the palm of your hand minus the fingers
1.5 ounces (45 grams): a lipstick or the size of your thumb
1 teaspoon (5 ml): your fingertip
1 tablespoon (15 ml): three fingertips
Finally, it’s worth mentioning that counting calories only allows you to evaluate your diet from a quantity perspective. It says very little about the qualityof what you eat.
When it comes to health, 100 calories from apples will affect your health differently than 100 calories from donuts.
Therefore, avoid picking foods solely based on their calorie content. Instead, make sure you also consider their vitamin and mineral contents. You can do so by favoring whole, minimally processed foods.