Many people are worried about gaining weight or raising blood sugar. They eat very little or even no carbohydrate staple food at night and rely on meat to satisfy their hunger. But is this model really beneficial to preventing obesity and diseases? Some new research evidence suggests that may not be the case...
Research interpretation
A study based on data from the U.S. National Health and Nutrition Examination Survey found thatIn people with diabetes, higher energy, fat, and protein intake at dinner than at breakfast is associated with higher diabetes mortality, cardiovascular disease mortality, and all-cause mortality.
The so-called all-cause death refers to all deaths caused by disease and aging, excluding accidents. The so-called "increased all-cause mortality" means "early death due to disease."
How was this research done?
The researchers analyzed data from two dietary surveys conducted between 2003 and 2014 among 4,699 adults with diabetes, including 2,413 men and 2,286 women. Then, the difference in caloric (energy) and nutrient intake between dinner and breakfast was calculated.
For example, if breakfast has 500 kcal and dinner has 800 kcal, the difference is 800-500=300 kcal.
Then, divide the difference between breakfast and dinner into five levels according to size. Then use the Cox proportional hazards regression model to evaluate the relationship between this difference and diabetes mortality, cardiovascular disease mortality, and all-cause mortality. I want to see how the mortality rate is different between people who eat breakfast and dinner about the same amount, and people who eat breakfast and dinner that are very different.
Let’s first compare from the perspective of the caloric difference between dinner and breakfast.
People with the biggest caloric difference between dinner and breakfast(>567kcal/d), and people who have about the same breakfast and dinner(≤67kcal/d)In comparison, the likelihood of dying from diabetes is 92% higher, and the likelihood of dying from cardiovascular disease is 69% higher!
Then compare the difference in fat energy supply ratio between dinner and breakfast. The so-called fat energy supply ratio refers to what proportion of calories in a meal comes from fat. The higher the value, the greasier the meal.
People with the largest difference in fat energy supply ratio between dinner and breakfast(The difference in fat energy supply ratio is >13.7%), and people who have little difference in the energy supply ratio of fat between two meals(The difference in fat energy supply ratio ≤ 2.5%)In comparison, cardiovascular disease mortality increased by 67%.
Especially those with the largest difference in the energy supply ratio between morning and evening unsaturated fatty acids had an 85% increase in cardiovascular disease mortality compared to those with the smallest difference! (Most of the unsaturated fatty acids come from vegetable oil for cooking)
So, what would be the result of comparing the protein energy supply of dinner and breakfast?
People with the largest difference in protein energy supply ratio between dinner and breakfast(Energy supply ratio difference＞7.7%), compared with breakfast protein energy supply is no less than dinner,Cardiovascular disease mortality increased by 96%, diabetes mortality increased by 92%, and all-cause mortality increased by 46%!
Examining the protein content, it was found that people whose breakfast and dinner had the largest difference in animal protein energy supply ratio (energy supply ratio difference >7.4%) had a 94% increased risk of dying from diabetes and a 49% increased risk of all-cause mortality.
Researchers unexpectedly discovered thatThe carbohydrates that people fear most, eating more at night than in the morning, have no significant correlation with all-cause mortality, diabetes mortality, and cardiovascular disease mortality.
So, if you switch part of the food from dinner to breakfast, and the total calories during the day remain the same, what will happen? To this end, the researchers established three sets of isocaloric substitution models. turn out:
If you take out 5% of the energy from dinner and eat it for breakfast, the risk ratio of diabetes and cardiovascular disease mortality will be reduced by 4% and 5% respectively;
If you reduce the fat energy in dinner by 5% and replace it with carbohydrates in breakfast, you can reduce the risk ratio of diabetes and cardiovascular disease mortality by 7% and 5% respectively;
If 5% of the energy from fat at dinner is replaced by protein at breakfast, the risk ratios for diabetes and cardiovascular disease mortality can be reduced by 9% and 12% respectively.
If 5% of the fat energy in dinner is replaced by unsaturated fatty acids in breakfast, the risk ratios of diabetes and cardiovascular disease mortality are reduced by 10% and 11% respectively;
If the protein energy of dinner is reduced by 5% and replaced by carbohydrate energy of breakfast, the risk ratio of diabetes and cardiovascular disease mortality can be reduced by 6% and 4%;
If you reduce the protein energy in dinner by 5% and move protein to breakfast, the risk ratio of diabetes and cardiovascular disease mortality can be reduced by 11%;
If you reduce the protein energy of dinner by 5% and replace it with unsaturated fatty acids at breakfast, the risk ratios of diabetes and cardiovascular disease mortality can be reduced by 10% and 11% respectively.
The above are the results of studies on people with diabetes, and they are survey results in the United States. So, will the same pattern apply to Chinese adults?
The same research team studied the health and nutrition survey data conducted in my country from 1997 to 2011 and found similar results-Eating more energy, protein and fat at dinner than at breakfast increases your risk of type 2 diabetes.
The study included 11,153 adults (5,848 women, 5,305 men), including 811 patients with type 2 diabetes. A dietary survey was conducted on the respondents for three consecutive days, and the difference in energy and nutrient intake between dinner and breakfast was also classified into five levels, and then the relationship between this difference and the risk of type 2 diabetes was explored.
The result is this:
Compared with people with the smallest difference in caloric intake between breakfast and dinner, the greater the difference, the higher the risk of type 2 diabetes, with the risk ratios increasing by 38%, 24%, 43% and 46% respectively.
Compared with people with the smallest difference in fat intake between breakfast and dinner, the greater the difference, the higher the risk of type 2 diabetes, with the risk ratios increasing by 34%, 38%, 67% and 85% respectively.
Compared with people with the smallest difference in protein intake between breakfast and dinner, the greater the difference, the higher the risk of type 2 diabetes, with the risk ratios increasing by 26%, 41%, 48% and 37% respectively.
No significant association was found between higher carbohydrate intake in the evening and the prevalence of diabetes.
Similarly, after establishing an isocaloric substitution model, the analysis found that:
If 5% of the total energy from dinner is moved to breakfast, the incidence of type 2 diabetes will be reduced by 7%;
If 5% of the fat energy in dinner is replaced by carbohydrates, protein and fat in breakfast respectively, the incidence of type 2 diabetes can be reduced by 9%, 5% and 7% respectively;
If 5% of the protein energy in dinner is replaced with carbohydrates and protein in breakfast, the incidence of type 2 diabetes can be reduced by 5%.
In layman’s terms, the results of these two studies are as follows:
1. Dinner takes up a large proportion of the day and has much more calories than breakfast. For diabetics, this way of eating will increase the risk of death from cardiovascular disease; for healthy people, this way of eating will increase the risk of diabetes.
2. Dinner is too greasy and has a high fat content, while breakfast is too light and has a low fat content. For people with diabetes, this eating method will also increase the risk of death from cardiovascular disease. Even eating more vegetable oils at night, mainly unsaturated fatty acids, will increase this risk of death. For healthy people, eating this way can increase the risk of diabetes.
3. Eating too much protein for dinner is detrimental. If you move the fat and protein from dinner to breakfast, or replace it with carbohydrates, you can significantly reduce the risk of death for diabetics. For healthy people, it can reduce the risk of diabetes.
4. Eating more breakfast is good for health, especially a larger proportion of protein in breakfast, which is helpful for people with diabetes to reduce the risk of all-cause death, and for healthy people, it is beneficial to reduce the risk of diabetes.
5.Eating starchy foods at night will not shorten the lifespan of diabetics, nor will it increase the risk of diabetes in healthy people. Therefore, it is suitable to eat a light meal with not too much animal protein, less fat, and a larger proportion of carbohydrates in the evening.
Although the number of dietary surveys in these two studies is not large enough, the evidence is not strong enough to predict long-term disease and survival status, but no matter what,The study only found the downsides of eating more energy, fat and protein at dinner, but not the downside of eating a regular carb dinner.
Why is this happening? Researchers believe that eating too much food at dinner may cause metabolic disorders by disrupting the expression of clock genes.Even if you consume the exact same food throughout the day, but the time of eating is different, the body's rhythm of regulating post-meal metabolism will be different when you eat in the morning or in the evening.
Even without considering circadian rhythm,Consuming too much protein and fat at night is also detrimental, affecting sleep quality and increasing the risk of gallstones.
If you eat too little staple food for dinner, the calories will mainly come from fat and protein. Protein is used to supply energy, which not only causes a waste of energy, but also produces more metabolic wastes, such as ammonia, urea, creatinine, etc. When the body needs to rest at night, the burden of processing metabolic wastes increases. Without the anti-ketogenic effect of carbohydrates, a large amount of fat oxidation for energy will generate ketone bodies, which will also increase the metabolic burden.
Especially for middle-aged and elderly people, due to the decline in liver and kidney function and the weakening of the ability to process metabolic waste, as a dietary habit, eating a large amount of protein and fat-based dinner for a long time may be detrimental to health.
These results suggest that traditional health regimen recommends that people eat a lighter meal at night, eat less meat, less fried food, drink multigrain porridge, eat potatoes more often, and eat a variety of vegetables. This eating pattern is scientifically justified.
If you are still continuing the pattern of eating modestly in the morning and overly rich meals in the evening, consider changing it~
It is recommended that you take out some of the high-protein and high-fat foods that were originally placed at dinner or even after dinner and eat them at breakfast., such as meat, such as cheese, such as nuts and oil seeds. If you occasionally want to eat sweets and snacks, you can also eat them in the morning, which will be less harmful to the body.As for dinner, eat whole grains and potatoes, and don't omit staple foods.This will not only help you sleep, but also help prevent illness.
References
[1] HanT, Gao J, WangL, et al. The Association of Energy and Macronutrient Intake at Dinner Versus Breakfast With Disease-Specific and All-Cause Mortality Among People With Diabetes: The U.S. National Health and Nutrition Examination Survey, 2003–2014. Diabetes Care, 2020.
[2] Ren X, Yang
[3] Asher G and Sassone-Corsi P. Time for Food: The Intimate Interplay between Nutrition, Metabolism, and the Circadian Clock. Cell, 2015.
[4] ArbleD, BassJ, LaposkyA, et al. CircadianTimingofFoodIntakeContributestoWeightGain.Obesity(SilverSpring, Md.), 2009.