Many versions of ketogenic diets exist, but all ban carb-rich foods. Some of these foods may be obvious: starches from both refined and whole grains like breads, cereals, pasta, rice, and cookies; potatoes, corn, and other starchy vegetables; and fruit juices. Some that may not be so obvious are beans, legumes, and most fruits. Most ketogenic plans allow foods high in saturated fat, such as fatty cuts of meat, processed meats, lard, and butter, as well as sources of unsaturated fats, such as nuts, seeds, avocados, plant oils, and oily fish. Depending on your source of information, ketogenic food lists may vary and even conflict.
I have pancreatitis, well controlled, which is the way I want to keep it. The biggest difficulty I have with keto is this: I eat a small portion of steel cut oats in the morning. When I don’t, within two days , I start having bleeding, dark in colour. My endrocrinolagest feels that I need the roughage in the steel cut oats to replete the bowel lining. I have great difficulty loosing weight, always have, even though I eat very clean, no junk food, never eat out, don’t like pop, don’t crave sugar, cook all food fresh. Any comment? Willing to try anything you can suggest.
Food reward regions in the brain programmed much of this physical dependence on processed foods and refined starches. But the body can reverse it. Acute bouts of aerobic exercise have been shown to significantly suppress appetite and hunger while increasing satiety and fullness.6 Exercise in the form of resistance (weight) training can enhance insulin sensitivity,7 which results in reduced insulin secretion.8 Less insulin helps bodies favor fat burning over fat storage.
Looking for that hearty crunch that’s packed full of flavor? Look no more. Instead of cracking open a box of Ritz or Cheez-Its, go ahead and make your own! You can make crackers from anything including flaxseed meal (featured in The RULED Book), chia seeds, or even almond flour to make your own homemade crunchy snacks with a delicious flavor of your own.
On a “strict” (standard) keto diet, fats typically provides about 70 percent to 80 percent of total daily calories, protein about 15 percent to 20 percent, and carbohydrates just around 5 percent. However, a more “moderate” approach to the keto diet is also a good option for many people that can allow for an easier transition into very low-carb eating and more flexibility (more on these types of plans below).
Bonnie J. Brehm, Randy J. Seeley, Stephen R. Daniels, and David A. D’Alessio, “A Randomized Trial Comparing a Very Low Carbohydrate Diet and a Calorie-Restricted Low Fat Diet on Body Weight and Cardiovascular Risk Factors in Healthy Women,” The Journal of Clinical Endocrinology & Metabolism: Vol 88, No 4; January 14, 2009. http://press.endocrine.org/doi/full/10.1210/jc.2002-021480.
“I am a family physician and co-author of the book The Diabetes Diet. I have been advocating a low-carb diet for patients for the last 16 years — for weight loss weight, cardiac risk reduction, and better blood sugar control in type 1 and 2 diabetes. The diet enables patients with type 1 diabetes to reduce their insulin needs, while patients with type 2 diabetes on insulin may be able to eliminate the drug completely. I leave the choice as to whether the diet needs to be ketogenic or not up to patients, depending on their motivation and goals.”
Don’t stick to chicken and steak just because you’re comfortable cooking them. Make dinner time the place where you can try new meats and recipes that increase your keto recipe resources. “At lunch and dinner, you can be creative and experiment,” Weaver says. “Just focus on cooking meat—pork, chicken, lamb, beef, or seafood. Meat is rich in iron and fish contains omega-3 fatty acids and vitamin D. Use only organic oils, such as avocado oil, coconut oil, and olive oil.” Read up on these things you have to know before starting the keto diet.
Hwu believes risks of cardiovascular disease and diabetes — which are both associated with high blood pressure, glucose and cholesterol — may be reduced by following the ketogenic diet, based on research. A recent study from Johns Hopkins found a ketogenic diet was not only safe, but effective for adults who had certain severe forms of epilepsy, supporting previous research.
But all those studies were very small, and not all research on the keto diet is as promising. One American Society for Clinical Nutrition study of 20 participants found that those on the diet didn’t lose more weight than those on a non-keto diet. But they did have fouler moods and higher levels of inflammation, which has been linked to a variety of conditions, including heart disease and cancer.
Sharon M. Nickols-Richardson, PhD, RD, , Mary Dean Coleman, PhD, RD, Joanne J. Volpe, Kathy W. Hosig, PhD, MPH, RD, “Perceived Hunger Is Lower and Weight Loss Is Greater in Overweight Premenopausal Women Consuming a Low-Carbohydrate/High-Protein vs High-Carbohydrate/Low-Fat Diet,” The Journal of Pediatrics: Vol 105, Issue 9: 1433–1437; September 2005. http://www.sciencedirect.com/science/article/pii/S000282230501151X.
Leftovers will be another thing we will take into consideration. Not only is it easier on you, but why put yourself through the hassle to cook the same food more than once? Breakfast is something I normally do leftover style, where I don’t have to worry about it in the morning and I certainly don’t have to stress about it. Grab some food out the fridge, pre-made for me, and head out the door. It doesn’t get much easier than that, does it?
Physical activity was determined by means of the International Physical Activity Questionnaire (IPAQ), which is used worldwide to indirectly evaluate an individual’s volumes of sedentary behavior and moderate to vigorous physical activity throughout the last seven-day week . It is readily available, very cost-effective, and can generate large data sets. The IPAQ comprises a set of 4 questionnaires. In this study, the short form of the IPAQ was employed (7 items). This measure assesses the types of intensity of physical activity and sitting time that people do as part of their daily lives, which is used to estimate total physical activity in metabolic equivalent task minutes per week (MET-min/week) and time spent sitting .
Gut health is extremely important for anyone looking to lose weight and increase overall health[*][*]. It is not uncommon for those who shift to a ketogenic diet to have a change in the production of bacteria in their colon (although not necessarily a bad thing – just a change)[*]. To help support this change and increase the healthy bacteria in your gut, try consuming more fermented foods such as sauerkraut, kimchi or kefir and/or supplement with a high-quality probiotic[*][*].
My husband is doing this diet and I was making him bean soup with sausage for dinner, but I’m reading beans are a food to avoid, even being a high fiber food is that really true? Beans were always a good I was encouraged to eat in many other diets. I’m new to keto and don’t want to hinder his process. Would appreciate your advice because I’ve already got the beans cooking. Oh they are the dry beans, not canned.
Positive science on ketosis coupled with personal successes passed by word-of-mouth have driven more people to explore the ketogenic diet, says Volek. More recently, the keto diet hints at having a promising therapeutic role in cancer, Alzheimer’s, Parkinson’s and polycystic ovary syndrome (PCOS). Research is still early in many areas, but Volek suspects there will more definitive answers on the wider scope of the diet’s benefits within the next decade.
12. Ferrer-Garcia M., Pla-Sanjuanelo J., Dakanalis A., Vilalta-Abella F., Riva G., Fernandez-Aranda F., Sanchez I., Ribas-Sabate J., Andreu-Gracia A., Escandon-Nagel N., et al. Eating behavior style predicts craving and anxiety experienced in food-related virtual environments by patients with eating disorders and healthy controls. Appetite. 2017;117:284–293. doi: 10.1016/j.appet.2017.07.007. [PubMed] [CrossRef] [Google Scholar]
An interesting effect on sexual function was induced by the nutritional intervention (Table S1; Figure 4). The EMAS-SF questionnaire reported no statistically significant changes for sexual activity in men (Figure 4A). However, the FSFI questionnaire for sexual activity in women evidenced that excitation (p = 0.043) and lubrication (p = 0.013) improved with statistical significance throughout the study. Moreover, from baseline to maximum ketosis, a statistically significant increase was observed in the score for the orgasmic domain (Figure 4B; 0.95; p = 0.034). Based on the FSFI mean total score, women included in this study showed sexual dysfunction (total score = 9.55) at baseline. This total score was improved at maximum of ketosis (total score = 10.48) and at the end of the nutritional intervention (total score = 9.8).
Wilder's colleague, paediatrician Mynie Gustav Peterman, later formulated the classic diet, with a ratio of one gram of protein per kilogram of body weight in children, 10–15 g of carbohydrate per day, and the remainder of calories from fat. Peterman's work in the 1920s established the techniques for induction and maintenance of the diet. Peterman documented positive effects (improved alertness, behaviour, and sleep) and adverse effects (nausea and vomiting due to excess ketosis). The diet proved to be very successful in children: Peterman reported in 1925 that 95% of 37 young patients had improved seizure control on the diet and 60% became seizure-free. By 1930, the diet had also been studied in 100 teenagers and adults. Clifford Joseph Barborka, Sr., also from the Mayo Clinic, reported that 56% of those older patients improved on the diet and 12% became seizure-free. Although the adult results are similar to modern studies of children, they did not compare as well to contemporary studies. Barborka concluded that adults were least likely to benefit from the diet, and the use of the ketogenic diet in adults was not studied again until 1999.
^ Freeman JM, Vining EP, Pillas DJ, Pyzik PL, Casey JC, Kelly LM. The efficacy of the ketogenic diet—1998: a prospective evaluation of intervention in 150 children. Pediatrics. 1998 Dec;102(6):1358–63. doi:10.1542/peds.102.6.1358. PMID 9832569. https://web.archive.org/web/20040629224858/http://www.hopkinsmedicine.org/press/1998/DECEMBER/981207.HTM Lay summary]—JHMI Office of Communications and Public Affairs. Updated 7 December 1998. Cited 6 March 2008.
Great point – the literature shows that ketogenic macro splits are very protein sparing for weight loss and the body will typically burn fat and glucose and spare lean mass. Dr. Jason Fung makes the analogy that it would be like stacking firewood for the winter and then when winter hits, deciding not to use the firewood and instead use the living room couch!
There are plant based healthy oils that have been in the food chain for thousands of years, including high-fat foods such as all nuts and seeds, avocados, extra virgin olive oil, sesame seed oil, black cumin seed oil (popular in the Middle East), palm oil sourced from sustainable producers, and the healthiest plant based fat of them all, coconut oil.
A related clinical diet for drug-resistant epilepsy is called the medium-chain triglyceride ketogenic diet, in which MCT oil is extensively used because it’s more ketogenic than long-chain triglycerides. (13) Another dietary therapy for epilepsy called Low Glycemic Index Treatment (LGIT) was developed in 2002 as an alternative to the keto diet. LGIT monitors the total amount of carbohydrates consumed daily, and focuses on carbohydrates that have a low glycemic index.) (14)
You’re ok with not so fast results and can remain disciplined.Every weight loss management plan needs an amount of sacrifice as well as a compromise from the dieter. But the ketosis approach may be one of the most challenging because it will change the most sacred of all eating routines among Western cultures: enjoying a full-dish meal. It's certainly no picnic, but the procedure can be done simpler having the right products and program, and the results can be spectacular.
What do LeBron James, Tim McGraw, and Halle Berry have in common? They all attribute their fab physiques to the keto diet plan, a high-fat, low-carb diet that is currently blowing up the internet. According to Google Trends, the keto diet peaked in popularity this week — and shows no signs of stopping. There are 4 million #keto posts on Instagram and more than 69 million keto diet recipes on Pinterest. As the ketogenic diet goes mainstream, some news outlets have described it as another unhealthy celebrity fad diet. Here’s what you need to know about the keto lifestyle — and how the Bulletproof Diet does it one better.
WY conceived, designed, and coordinated the study; participated in data collection; performed statistical analysis; and drafted the manuscript. MF assisted with study design, performed data collection, and helped to draft the manuscript. AC analyzed the food records. MV assisted with study/intervention design and safety monitoring. EW participated in the conception and design of the study, and assisted with the statistical analysis. All authors read and approved the final manuscript.
Touting their discovery as “a great step forward in weight loss history,” the panel were quick to offer up their hard earned cash to back the entrepreneurial pair. “We were shocked. The most we were hoping for was some advice…we weren’t even sure that we would manage to get any investors,” explained Samantha. After outstanding offers from each panel member, the sisters burst into tears.
Because some cancer cells are inefficient in processing ketone bodies for energy, the ketogenic diet has also been suggested as a treatment for cancer. A 2018 review looked at the evidence from preclinical and clinical studies of ketogenic diets in cancer therapy. The clinical studies in humans are typically very small, with some providing weak evidence for anti-tumour effect, particularly for glioblastoma, but in other cancers and studies, no anti-tumour effect was seen. Taken together, results from preclinical studies, albeit sometimes contradictory, tend to support an anti-tumor effect rather than a pro-tumor effect of the KD for most solid cancers.
If you're new to keto, watch out for hidden carbs. Generally, dairy products and nuts are a good way to meet your daily fat intake, but know that some of those items may contain more carbohydrates than you think. For example, yogurt topped with nuts may seem like a great keto-friendly snack, but a 5.3 ounce serving of plain yogurt has 12 grams of carbohydrates. Vanilla flavored yogurt has 24 grams of carbohydrates. Add an ounce of cashews, weighing in at nearly nine grams of carbs, and you’re up to 21 to 33 grams of carbs for that snack, which could knock you out of ketosis. Be sure to read nutrition labels carefully and pay careful attention to serving sizes. Track foods using a keto-specific app like Senza or KetoDiet can help you stay within your recommended daily carb intake.
To figure out how many fat grams specifically you want, you would take the total number of calories it takes to maintain your body weight (normally around 14-16 calories per pound of body weight). Subtract your protein calories from that number and then divide by 9 (number of calories per gram of fat). This should give you how many total fat grams you need to eat per day.
Cutting back on protein is one of the largest challenges to the diet. Because high levels of protein in the diet can turn into glucose in a process called gluconeogenesis, the keto theory says too much protein in the diet can mean too much glucose, whisking you out of ketosis. That’s why bacon, which has a ton of fat but not a lot of protein is a preferred food over chicken breast, which is high in protein with very little fat.
Gary D. Foster, Ph.D., Holly R. Wyatt, M.D., James O. Hill, Ph.D., Brian G. McGuckin, Ed.M., Carrie Brill, B.S., B. Selma Mohammed, M.D., Ph.D., Philippe O. Szapary, M.D., Daniel J. Rader, M.D., Joel S. Edman, D.Sc., and Samuel Klein, M.D., “A Randomized Trial of a Low-Carbohydrate Diet for Obesity — NEJM,” N Engl J Med 2003; 348:2082- 2090. http://www.nejm.org/doi/full/10.1056/NEJMoa022207.
When the craving for alcohol was evaluated, no statistically significant changes were observed in the MACS scores through the nutritional intervention, taking all patients together (Table S1). However, when the analysis was performed considering the gender of participants in the study, men experienced a significant decrease in the total score through the study (p = 0.047). This decrease was more notable in the maximum ketosis phase as compared with baseline (−15.14; p = 0.047). Moreover, a statistically significant reduction was observed in the lack of inhibition item (−27.19; p = 0.042).
While in ketosis, your body effectively uses fat for fuel. In general, the daily intake of net carbs required to enter ketosis could vary from 20 to 100 grams per day. Most people, who have experienced ketosis, claim to have reached that state at about 20-50 grams of net carbs per day. I'd suggest you start at 20-30 grams and see how you can adjust it for your needs.
Except : I feel like [email protected]! Almost everyday... not all day but at some point mid afternoon onwards I start feeling discombobulated, uncomfortable, weak and a little anxious ... electrolytes, more fat or calories i tweaked everything to no avail. it's a weird discomfort in my body and I'm wondering if it just doesn't enjoy ketosis. Last night I felt so bad like i was about to collapse I ate 4 spoons of plain white rice just to kick myself out of keto ( was still only 40gr of total carbs though ) and I felt significantly better and as per keto sticks I'm still dark pink.
Finally, the accuracy of MF-BIA and ADP in the estimation of body composition was studied in relation to DXA. As shown in Table 2, the unadjusted regression coefficients for FM, FM%, and FFM were consistently higher with MF-BIA in comparison with ADP throughout the study. Specifically, regression coefficients for MF-BIA were high (r2 > 0.8) for FM and FFM, whereas those regression coefficients for FM% were slightly lower (r2 > 0.7). However, most of the regression coefficients using ADP were lower (r2 < 0.7) for FM, FM%, and FFM. A similar pattern was observed when adjusting for age and sex. The regression coefficients for both MF-BIA and ADP decreased with weight loss.
Hey Donna, yes frozen veggies are totally fine! And my best advice would be to just jump right back into it and not dwell on the past! I would recommend tracking your carbs and making sure they are low enough to get back into keto, maybe try some intermittent fasting as well. It will take a few days to get back on track but just stick with it and focus on your goals!
In the early 1900s Frederick Madison Allen developed a highly restrictive short term regime which was described by Walter R. Steiner at the 1916 annual convention of the Connecticut State Medical Society as The Starvation Treatment of Diabetes Mellitus.:176–177 People showing very high urine glucose levels were confined to bed and restricted to an unlimited supply of water, coffee, tea, and clear meat broth until their urine was "sugar free"; this took two to four days but sometimes up to eight.:177 After the person's urine was sugar-free food was re-introduced; first only vegetables with less than 5g of carbohydrate per day, eventually adding fruits and grains to build up to 3g of carbohydrate per kilogram of body weight. Then eggs and meat were added, building up to 1g of protein/kg of body weight per day, then fat was added to the point where the person stopped losing weight or a maximum of 40 calories of fat per kilogram per day was reached. The process was halted if sugar appeared in the person's urine.:177–178 This diet was often administered in a hospital in order to better ensure compliance and safety.:179
^ Ketogenic "eggnog" is used during induction and is a drink with the required ketogenic ratio. For example, a 4:1 ratio eggnog would contain 60 g of 36% heavy whipping cream, 25 g pasteurised raw egg, saccharin and vanilla flavour. This contains 245 kcal (1,025 kJ), 4 g protein, 2 g carbohydrate and 24 g fat (24:6 = 4:1). The eggnog may also be cooked to make a custard, or frozen to make ice cream.
The popular belief that high-fat diets cause obesity and several other diseases such as coronary heart disease, diabetes, and cancer has not been observed in recent epidemiological studies. Studies carried out in animals that were fed high-fat diets did not show a specific causal relationship between dietary fat and obesity. On the contrary, very-low-carbohydrate and high-fat diets such as the ketogenic diet have shown to beneficial to weight loss.
GLUT1 deficiency is the technical term for what some medical practitioners are now calling diabetes 3. It’s the brain cell’s insulin resistance or a deficiency of glucose transport to brain cells. It impairs cellular metabolism in the brain, and is considered a source of Alzheimer’s disease, Multiple sclerosis, and epileptic seizures, among others.
With funding from the Laura and John Arnold Foundation, in 2012 Taubes co-founded the Nutrition Science Initiative (NuSI), with the aim of raising over $200 million to undertake a "Manhattan Project for nutrition" and validate the hypothesis. Intermediate results, published in the American Journal of Clinical Nutrition did not provide convincing evidence of any advantage to a low-carbohydrate diet as compared to diets of other composition – ultimately a very low-calorie, ketogenic diet (of 5% carbohydrate) "was not associated with significant loss of fat mass" compared to a non-specialized diet with the same calories; there was no useful "metabolic advantage". In 2017 Kevin Hall, a NIH researcher hired to assist with the project, wrote that the carbohydrate-insulin hypothesis had been falsified by experiment. Hall wrote "the rise in obesity prevalence may be primarily due to increased consumption of refined carbohydrates, but the mechanisms are likely to be quite different from those proposed by the carbohydrate–insulin model".
Overweight individuals with metabolic syndrome, insulin resistance, and type 2 diabetes are likely to see improvements in the clinical markers of disease risk with a well-formulated very-low-carbohydrate diet. Glucose control improves due to less glucose introduction and improved insulin sensitivity. In addition to reducing weight, especially truncal obesity and insulin resistance, low-carb diets also may help improve blood pressure, blood glucose regulation, triglycerides, and HDL cholesterol levels. However, LDL cholesterol may increase on this diet.
The ketogenic diet first gained fame through its effectiveness for weight loss. The high-fat, low-carb diet promotes nutritional ketosis–a normal metabolic state marked by moderate levels of ketones in the blood. The idea with carb restriction in terms of weight loss is that it prompts the release of body fat to be burned or converted to ketones for energy (extra dietary fat also contributes to ketone production).
All of the patients followed a VLCK diet according to a commercial weight loss program (PNK Method), which includes lifestyle and behavioral modification support. The intervention included an evaluation by the specialist physician conducting the study and assessment by an expert dietician. All patients underwent a structured program of physical exercise with external supervision (16). This method is based on high-biological-value protein preparations obtained from cow milk, soya, avian eggs, green peas, and cereals. Each preparation contained 15 g protein, 4 g carbohydrates, 3 g fat, and 50 mg docosahexaenoic acid, and provided 90 to 100 kcal (16).
Dr. Campos, it is unfortunate that you retain the medical community’s negative stance on the ketogenic diet, probably picked up in medical school when you studied ketoacidosis, in the midst of an obesity and type II diabetes epidemic that is growing every year, especially among populations who will never see the Harvard Health Letter. The medical community has failed in reversing this trend, especially among children, and the public is picking up the tab, in the form of higher health insurance premiums to treat chronic metabolic diseases which doctors cannot cure. The ketogenic diet does not bid its adherents to eat unhealthy processed meats, and the green leafy vegetables that it emphasizes are important in a number of nutritional deficiencies. People lose weight on the ketogenic diet, they lose their craving for sugar, they feel more satiety, they may become less depressed, their insulin receptors sensitivity is improved, and these are all the good outcomes you fail to mention. There is a growing body of research which demonstrates the neuroprotective effects of the ketogenic diet to slow cancer progression, as well as diseases like Parkinson’s and Alzheimer’s, for which there are no effective medical treatments. Please respect your patients by providing them with evidence-based medical outcomes, not opinions.
Over the past century, ketogenic diets have also been used as natural remedies to treat and even help reverse neurological disorders and cognitive impairments, including epilepsy, Alzheimer’s symptoms, manic depression and anxiety. Research shows that cutting off glucose levels with a very low-carb diet makes your body produce ketones for fuel. This change can help to reverse neurological disorders and cognitive impairment, including inducing seizure control. The brain is able to use this alternative source of energy instead of the cellular energy pathways that aren’t functioning normally in patients with brain disorders.
For patients who benefit, half achieve a seizure reduction within five days (if the diet starts with an initial fast of one to two days), three-quarters achieve a reduction within two weeks, and 90% achieve a reduction within 23 days. If the diet does not begin with a fast, the time for half of the patients to achieve an improvement is longer (two weeks), but the long-term seizure reduction rates are unaffected. Parents are encouraged to persist with the diet for at least three months before any final consideration is made regarding efficacy.
Thank you for your wonderful informational website. I've been following ketogenics since Sept 2017 and I've now lost 31 pounds on Keto, but also lost an additional 10 pounds prior to changing to low carb, no sugar ketogenics. It has been a long time since I've not lived to eat. It seemed that prior to my weight loss I was always hungry and ate for no good reason. Now all has changed. I do not eat processed foods at all only green veggies. Thanks for all the recipes and "how to" information.
Much of the research into low-carbohydrate dieting has been of poor quality and studies which reported large effects have garnered disproportionate attention in comparison to those which are methodologically sound. Higher quality studies tend to find no meaningful difference in outcome between low-fat and low-carbohydrate dieting. Low-quality meta-analyses have tended to report favourably on the effect of low-carbohydrate diets: a systematic review found that 9 out of 10 meta-analyses with positive conclusions were affected by publication bias.
How it’s done: Warm up the LEVL or Ketonix meter by plugging it in. Blow into it and wait for the flashing light indicating it’s reading your acetone levels. The software or the color and speed of the flashing light would tell your reading: green for least acetone, red for most acetone, less flashing for less acetone per color, more flashing for more acetone per color.
The changes in the variables of the study were analyzed through repeated-measures ANOVA (the within-subjects factor included 4 measurements), defining polynomial contrast to explore potential linear, quadratic, and cubic trends (3-order polynomial trends were considered due to the 4-level measurements), and post-hoc pairwise comparisons employing Tukey’s adjustment for multiple comparisons. Effect size for each pairwise comparison was based on Cohen’s-d coefficient, considering poor effect size for |d| > 0.20, medium/moderate for |d| > 0.50, and large/good for |d| > 0.80 .
The American Academy of Family Physicians defines low-carbohydrate diets as diets that restrict carbohydrate intake to 20 to 60 grams per day, typically less than 20% of caloric intake. A 2016 review of low-carbohydrate diets classified diets with 50g of carbohydrate per day (less than 10% of total calories) as "very low" and diets with 40% of calories from carbohydrates as "mild" low-carbohydrate diets. In a 2015 review Richard D. Feinman and colleagues proposed that a very low carbohydrate diet had less that 10% caloric intake from carbohydrate, a low carbohydrate diet less than 26%, a medium carbohydrate diet less than 45%, and a high carbohydrate diet more than 45%.
Health experts think that the first law is relevant to why we get fat because they say to themselves and then to us, as the The New York Times did, “Those who consume more calories than they expend in energy will gain weight.” This is true. It has to be. To get fatter and heavier, we have to overeat. We have to consume more calories than we expend. That’s a given. But thermodynamics tells us nothing about why this happens, why we consume more calories than we expend. It only says that if we do, we will get heavier, and if we get heavier, then we did.
I was a Corpsman (not a corpse-man as some recent somewhat fanatical president would say), and I can tell you many stories of Marines and Sailors who maintained restrictive diets (aka picky eaters). Most obvious was lack of sustaining energy (hypoglycemia) at mile 15 (with 80lbs of gear including a 6.5lb rifle and 200 rnds of ammo, etc.) and depletion of essential vitamins, electrolyte imbalance. They were always the first to collapse and have to hear me scold “see I told you so.” An IV of D5W usually does the trick (D is for dextrose, OMG!)