Sabtu, 27 Maret 2010
Talkin' Bout A Revolution...Jamie Oliver is much louder than a whisper!
So I just finished watching the premiere episode of "Jamie Oliver's Food Revolution". It is a new show on ABC that chronicles the journey of English chef Jamie Oliver as he tries to change the eating habits of residents in Huntington, West Virginia. Huntington was recently crowned the most unhealthy city in America.
It is obvious that Jamie has good intentions. He has left his family for several months to work on this project. He is especially concerned about the quality of food being served in the Huntington schools. However, my reaction to the first episode was "No, no, no! Stop what you're doing and talk to these people first!"
The most important part of any public health intervention is getting to know the community you are working with. The worst thing you can do is come in as an "outsider" and start barking orders. Some questions you should ask before getting started are: How does this community operate? Who makes the decisions? What are some of the barriers to serving fresh food in schools? What are the USDA guidelines? (which Jamie knows nothing about) Who are the individuals you want/need to get on board with your idea? How do the parents feel about their children's eating habits? How can you get their buy-in? What would be a realistic timeline for assessment/buy-in before trying to implement change?
Jamie went about this all backwards (which may very well have been to increase drama for a TV show, but it is still a great example of "what not to do"). His first day in town he was told he was viewed as an "outsider" by the trusted radio host...and still proceeded to go into the elementary school and lecture the chefs on how disgusting the food is (after only observing them for one day). And he's surprised he's getting push back on his efforts?! The only small victory he has is creating a partnership with "Pastor Steve" at the local Baptist church. Steve is a trusted leader in the community and knows the families and their challenges very well.
Too bad Jamie did not look to better models of this kind of community effort. Shape Up Somerville (Somerville, MA) began as a community based research study at Tufts University targeting 1st through 3rd graders in the Somerville Public Schools. Today there is Coordinator working on active and healthy living programs supported by the Health Department and a Taskforce that is a collaboration of over 11 initiatives and 25 stakeholders involved in working on various interventions across the city. Program components include a focus on the school lunch program, local restaurants, walk ability and safe routes to school, etc. (I'll give a shout out here to one of my public health heroes- Julia Bloom- who helped Tufts bring this model to more rural communities across the country!)
Shape Up Somerville represents a strong program that began with a strong base. The original program engaged key stakeholders and did not try to change the community without first finding out how it worked. The community and parent outreach were an obvious key to success...where that aspect is basically forgotten in the "Food Revolution". Jamie just seems like one man on a mission to change. At the end of the episode Jamie is visibly upset and says "they don't know why I'm here". Yeah- that's because you're an outsider lecturing them on how they should raise their kids!
I'll probably watch the second episode where he actually starts to engage the community...how about you?
Kamis, 25 Maret 2010
Interesting Articles in the AJCN
1. Dr. Neil D. Barnard reviews food consumption patterns in the US from 1909 to 2007 (1). This is something I've written about a number of times. The most notable change is that industrial seed oil use has increased by more than 3-fold in the last 40 years, and even more in the last 100 although he doesn't provide those numbers. Butter and lard use declined sharply. Meat consumption is up, but the increase comes exclusively from poultry because we're eating the same amount of red meat we always have. Grain consumption is down, although it peaked around 1900 so it may not be a fair comparison with today:
In the late 1800s, wheat flours became more popular and available due to the introduction of new [high-gluten] wheat varieties, [low extraction] milling techniques, and transport methods, and during this time new breakfast cereals were introduced by John Harvey Kellogg, CW Post, and the Quaker Oats Company. Thereafter, however, per capita availability of flour and cereal products gradually dropped as increased prosperity, improved mechanization, and transport (eg, refrigerated railway cars) increased competition from other food groups. [Then they partially rebounded in the last 40 years]2. Dr. S.C. Larsson published a paper showing that in Sweden, multivitamin use is associated with a slightly higher risk of breast cancer (2).
3. Soy protein and isoflavones, which have been proposed to do everything from increase bone mineral density to fight cancer, are slowly falling out of favor. Dr. Z.M. Liu and colleagues show that soy protein and/or isoflavone supplementation has no effect on insulin sensitivity or glucose tolerance in a 6 month trial (3). This follows a recent trial showing that isoflavones have no effect on bone mineral density.
4. Dr. Ines Birlouez-Aragon and colleagues showed that high-heat cooked (fried and sauteed) foods increase risk factors for diabetes and cardiovascular disease (insulin resistance, cholesterol, triglycerides), compared to low-heat cooked foods (steamed, stewed) in a one-month trial (4). The high-heat diet also reduced serum levels of long-chain omega-3 fatty acids and vitamins C and E.
5. Dr. Katharina Nimptsch and colleagues showed that higher menaquinone (vitamin K2) intake is associated with a lower cancer incidence and lower cancer mortality in Europeans (5). Most of their K2 came from cheese.
6. And finally, Dr. Zhaoping Li and colleagues showed that cooking meat with an herb and spice blend reduced the levels of oxidized fat during cooking, and reduced serum and urinary markers of lipid oxidation in people eating the meat (6).
Selasa, 23 Maret 2010
New Review of Controlled Trials Replacing Saturated fat with Industrial Seed Oils
These findings provide evidence that consuming PUFA in place of SFA reduces CHD events in RCTs. This suggests that rather than trying to lower PUFA consumption, a shift toward greater population PUFA consumption in place of SFA would significantly reduce rates of CHD.Looking at the studies they included in their analysis (and at those they excluded), it looks like they did a nice job cherry picking. For example:
- They included the Finnish Mental Hospital trial, which is a terrible trial for a number of reasons. It wasn't randomized, properly controlled, or blinded*. Thus, it doesn't fit the authors' stated inclusion criteria, but they included it in their analysis anyway**. Besides, the magnitude of the result has never been replicated by better trials-- not even close.
- They included two trials that changed more than just the proportion of SFA to PUFA. For example, the Oslo Diet-heart trial replaced animal fat with seed oils, but also increased fruit, nut, vegetable and fish intake, while reducing trans fat margarine intake. The STARS trial increased both omega-6 and omega-3, reduced processed food intake, and increased fruit and vegetable intake. These obviously aren't controlled trials isolating the issue of dietary fat substitution. If you subtract the four inappropriate trials from their analysis, which is half the studies they analyzed, the significant result disappears. Those four just happened to show the largest reduction in heart attack mortality...
- They excluded the Rose et al. corn oil trial and the Sydney Diet-heart trial. Both found a large increase in total mortality from replacing animal fat with seed oils, and the Rose trial found a large increase in heart attack deaths (the Sydney trial reported total mortality but not CHD deaths).
So basically, even if the authors' conclusion were correct, you overhaul your whole diet and replace natural foods with industrial foods, and...? You reduce your 10-year risk of having a heart attack from 10 percent to 9 percent. Without affecting your overall risk of dying. The paper states that the interventions didn't affect overall mortality.
* Not even single blinded. Autopsies were not conducted in a blinded manner. Physicians knew which hospital the cadavers came from, because autopsies were done on-site. There is some confusion about this point because the second paper states that physicians interpreted the autopsy reports in a blinded manner. But that doesn't make it blinded, since the autopsies weren't blinded. The patients were also not blinded, though this is hard to accomplish with a study like this.
** They refer to it as "cluster randomized", which I feel is a misuse of that term. The investigators definitely didn't randomize the individual patients: whichever hospital a person was being treated in, that's the food he/she ate. There were only two hospitals, so "cluster randomization" in this case would just refer to deciding which hospital got the intervention first. I don't think this counts as cluster randomization. An example of cluster randomization would be if you had 10 hospitals, and you randomized which hospital received which treatment first. It's analogous to individual randomization but on a group scale.
Sabtu, 20 Maret 2010
Fatty Liver: It's not Just for Grown-ups Anymore
NAFLD is an excessive accumulation of fat in the liver that impairs its function and can lead to severe liver inflammation (NASH), and in a small percentage of people, liver cancer. An estimated 20-30% of people in industrial nations suffer from NAFLD, a shockingly high prevalence (1).
I previously posted on dietary factors I believe are involved in NAFLD. In rodents, feeding a large amount of sugar or industrial seed oils (corn oil, etc.) promotes NAFLD, whereas fats such as butter and coconut oil do not (2). In human infants, enteric feeding with industrial seed oils causes severe liver damage, whereas the same amount of fat from fish oil doesn't, and can even reverse the damage done by seed oils (3). [2013 update: obesity is probably the main contributor to NAFLD. Obesity is associated with ectopic fat deposition in a number of organs, including the liver]
So basically, I think excessive sugar and industrial oils could be involved NAFLD, and if you look at diet trends in the US over the last 40 years, they're consistent with the idea.
I recently came across a study that examined the diet of Canadian children with NAFLD (6). The children had a high sugar intake, a typical (i.e., high) omega-6 intake, and a low omega-3 intake. The authors claimed that the children also had a high saturated fat intake, but at 10.5% of calories, they were almost eating to the American Heart Association's "Step I" diet recommendations**! Total fat intake was also low.
High sugar consumption was associated with a larger waist circumference, insulin resistance, lower adiponectin and elevated markers of inflammation. High omega-6 intake was associated with markers of inflammation. Low omega-3 intake was associated with insulin resistance and elevated liver enzymes. Saturated fat intake presumably had no relation to any of these markers, since they didn't mention it in the text.
These children with NAFLD, who were all insulin resistant and mostly obese, had diets high in omega-6, high in sugar, and low in omega-3. This is consistent with the idea that these three factors, which have all been moving in the wrong direction in the last 40 years, contribute to NAFLD.
* Fatty liver was assessed by liver enzymes, admittedly not a perfect test. However, elevated liver enzymes do correlate fairly well with NAFLD.
** Steps I and II were replaced by new diet advice in 2000. The AHA now recommends keeping saturated fat below 7% of calories. However, the new recommendations focus mostly on eating real food rather than avoiding saturated fat and cholesterol.
Rabu, 17 Maret 2010
Book Review: The Primal Blueprint
In 2009, Mark published his long-awaited book The Primal Blueprint. He self-published the book, which has advantages and disadvantages. The big advantage is that you aren't subject to the sometimes onerous demands of publishers, who attempt to maximize sales at Barnes and Noble. The front cover sports a simple picture of Mark, rather than a sunbaked swimsuit model, and the back cover offers no ridiculous claims of instant beauty and fat loss.
The drawback of self-publishing is it's more difficult to break into a wider market. That's why Mark has asked me to publish my review of his book today. He's trying to push it up in the Amazon.com rankings so that it gets a broader exposure. If you've been thinking about buying Mark's book, now is a good time to do it. If you order it from Amazon.com on March 17th, Mark is offering to sweeten the deal with some freebies on his site Mark's Daily Apple. Full disclosure: I'm not getting anything out of this, I'm simply mentioning it because I was reviewing Mark's book anyway and I thought some readers might enjoy it.
The Primal Blueprint is not a weight loss or diet book, it's a lifestyle program with an evolutionary slant. Mark uses the example of historical and contemporary hunter-gatherers as a model, and attempts to apply those lessons to life in the 21st century. He does it in a way that's empowering accessible to nearly everyone. To illustrate his points, he uses the example of an archetypal hunter-gatherer called Grok, and his 21st century mirror image, the Korg family.
The diet section will be familiar to anyone who has read about "paleolithic"-type diets. He advocates eating meats including organs, seafood, eggs, nuts, abundant vegetables, and fruit. He also suggests avoiding grains, legumes, dairy (although he's not very militant about this one), processed food in general, and reducing carbohydrate to less than 150 grams per day. I like his diet suggestions because they focus on real food. Mark is not a drill sergeant. He tries to create a plan that will be sustainable in the long run, by staying positive and allowing for cheats.
We part ways on the issue of carbohydrate. He suggests that eating more than 150 grams of carbohydrate per day leads to fat gain and disease, whereas I feel that position is untenable in light of what we know of non-industrial cultures (including some relatively high-carbohydrate hunter-gatherers). Although carbohydrate restriction (or at least wheat and sugar restriction) does have its place in treating obesity and metabolic dysfunction in modern populations, ultimately I don't think it's necessary for the prevention of those same problems, and it can even be counterproductive in some cases. Mark does acknowledge that refined carbohydrates are the main culprits.
The book's diet section also recommends nutritional supplements, including a multivitamin/mineral, antioxidant supplement, probiotics, protein powder and fish oil. I'm not a big proponent of supplementation. I'm also a bit of a hypocrite because I do take small doses of fish oil (when I haven't had seafood recently), and vitamin D in wintertime. But I can't get behind protein powders and antioxidant supplements.
Mark's suggestions for exercise, sun exposure, sleep and stress management make good sense to me. In a nutshell: do all three, but keep the exercise varied and don't overdo it. As a former high-level endurance athlete, he has a lot of credibility here. He puts everything in a format that's practical, accessible and empowering.
I think The Primal Blueprint is a useful book for a person who wants to maintain or improve her health. Although we disagree on the issue of carbohydrate, the diet and lifestyle advice is solid and will definitely be a vast improvement over what the average person is doing. The Primal Blueprint is not an academic book, nor does it attempt to be. It doesn't contain many references (although it does contain some), and it won't satisfy someone looking for an in-depth discussion of the scientific literature. However, it's perfect for someone who's getting started and needs guidance, or who simply wants a more comprehensive source than reading blog snippets. It would make a great gift for that family member or friend who's been asking how you stay in such good shape.
Kamis, 11 Maret 2010
Vitamin D May Prevent Flu and Asthma
They also found that in the subset of children not already taking vitamin D supplements, the effect was greater, with unsupplemented children contracting nearly three times as many influenza A infections as children receiving vitamin D. They didn't analyze the influenza B or total influenza incidence in that way, so we don't know if prior supplementation makes a difference there.
The most striking finding of the paper is that the vitamin D group suffered from 6 times fewer asthma attacks than the placebo group. This needs to be repeated but it's consistent with other data and I find it very encouraging.
The paper did have some limitations. They didn't measure vitamin D status so they have no way to know exactly how effective their pill-based supplements were.
Another problem is that they began collecting data immediately after beginning supplementation. Vitamin D is a fat-soluble vitamin that can take 3 months to reach maximum concentration in the body following supplementation. By the time the children were reaching their maximum serum concentration of vitamin D, the trial was over. It would be nice to see the next trial begin supplementation in the fall and look at flu incidence in the winter.
This paper comes on the heels of another showing that vitamin D is necessary for the activation of an immune cell called the killer T cell (2). These are important for resistance to infections and cancer. Overall, these papers add to the accumulating evidence that vitamin D is important for the proper functioning of the human immune system. However, mice may not be the best model for use in studying vitamin D biology. From the first paper:
The evolution of different mechanisms for the regulation of PLC-γ1 activity in human and mouse T cells parallels the development of divergent VDR-dependent and VDR-independent antimicrobial pathways in human and mouse macrophages31, respectively, and may reflect the fact that mice are nocturnal animals with fur and humans are daytime creatures that synthesize vitamin D in the skin after exposure to ultraviolet light.In other words, mice don't use vitamin D in the same way as humans because they have a different evolutionary relationship to it.
Rabu, 10 Maret 2010
A False Dichotomy
Any time the discussion reaches this point, it stops providing us anything useful. The argument is a false dichotomy, one in which neither answer is correct. The correct answer is (c): none of the above. Some aspects of hunter-gatherer life are preferable to ours, and some aspects of our lives are preferable to theirs. Understanding that we spent a lot of evolutionary time as hunter-gatherers, as well as a few thousand years in small, tightly knit agricultural communities, may be useful in understanding how to work constructively with our own bodies and minds in the modern world.
So please, let's leave behind the false dichotomy and foster a more nuanced understanding of the lives our ancestors led.
Selasa, 09 Maret 2010
Technology: Building Social Connections or Breaking Them Down?
Last week, a friend at work told me that she had given up watching TV for Lent. She said "every time I give up TV, my quality of life goes up". I thought of her immediately today as I read this new article in TIME, "Logged on, checked out...of relationships?" The article discusses a study (published in the March issue of the journal Archives of Pediatrics & Adolescent Medicine) which studied adolescents during two periods of time (1988 and 2004). The adolescents who spent more time watching TV or playing video games were more likely to report lower quality relationships compared with those who logged less screen time.
I find this fascinating because I have followed the debate among colleagues and friends regarding the increase in the use of technology and its impact on social connections. For example, kids that may be "outcasts" at school may find friends online. They may have hundreds of Facebook "friends". They may find lots of kids with similar interests by joining "groups" online. However, one has to ask, are Facebook friends "real"? I personally have 355 friends on Facebook, but would only consider about 10 of those people close friends in my day to day life. Is it worth it to focus your time and attention to online activities (as noted above) to the detriment of your "real life" relationships with friends and family?
In looking at how social connectedness can be a protective factor for things like suicide, the question has also come up: "Is it the quantity or quality of relationships that really count?" In research on college students, studies like Healthy Minds are beginning to indicate that it is the quality that counts. However, unlike my previous posts where it has been easy for me to take one side or the other...I'm torn about this issue. The authors of the above study were as well...they note that there is an obvious correlation between online activities and relationship quality, but the causal link is not clear.
Therefore, I believe it is probably some happy balance that is best. Facebook friends and groups are not all superficial and time wasters. People can connect (or in many cases, "reconnect") with friends and colleagues with shared histories or interests. I've seen Friends post a concerning or unsafe status and 20 people jump in with words of encouragement or offers of help...which is wonderful. On the flip side, it helps to turn the computer or TV off and enjoy the world around us...strengthen those connections with those we live with, eat dinner away from the TV, etc. And of course on that note, I'll log off. LOST starts at 9pm ;)
Senin, 08 Maret 2010
The Paleolithic Mind
I'm totally ignorant of the scientific literature on this, but the way I see it, there are at least two main sources of psychological stress in the modern world for which we aren't well equipped as human beings:
- Being eternally and inescapably subordinate in a large social structure
- Having too many responsibilities such as possessions and obligations
The Hadza do not engage in warfare [although they do have homicide]. They've never lived densely enough to be seriously threatened by an infectious outbreak. They have no known history of famine; rather, there is evidence of people from a farming group coming to live with them during a time of crop failure. The Hadza diet remains even today more stable and varied than that of most of the world's citizens. They enjoy an extraordinary amount of leisure time. Anthropologists have estimated that they "work"—actively pursue food—four to six hours a day. And over all these thousands of years, they've left hardly more than a footprint on the land.This isn't intended to idealize their lifestyle, but to point out that being a hunter-gatherer has its advantages. One of these is a minimal social structure in which each person is has full authority over himself:
The Hadza recognize no official leaders. Camps are traditionally named after a senior male (hence, Onwas's camp), but this honor does not confer any particular power. Individual autonomy is the hallmark of the Hadza. No Hadza adult has authority over any other. None has more wealth; or, rather, they all have no wealth. There are few social obligations—no birthdays, no religious holidays, no anniversaries.Even "marriage" doesn't carry much obligation. The author describes the Hadza as "serial monogamists". The idea of an eternal bond between two individuals doesn't exist. Women are not subordinate to men:
Gender roles are distinct, but for women there is none of the forced subservience knit into many other cultures. A significant number of Hadza women who marry out of the group soon return, unwilling to accept bullying treatment. Among the Hadza, women are frequently the ones who initiate a breakup—woe to the man who proves himself an incompetent hunter or treats his wife poorly. In Onwas's camp, some of the loudest, brashest members were women.Contrast this with modern civilizations in which everyone has a boss-- whether it's at a job, in a marriage or under your country's legal system. I think this feeling of perpetual subordination is destructive to an animal such as ourselves, that has spent so much of its existence mostly free of these pressures.
The author says this about their possessions:
Traditional Hadza, like Onwas and his camp mates, live almost entirely free of possessions. The things they own—a cooking pot, a water container, an ax—can be wrapped in a blanket and carried over a shoulder.This resembles other African hunter-gatherer groups that have few and simple tools. From the book The !Kung San: Men, Women and Work in a Foraging Society:
!Kung tools are few in number, lightweight, made from locally available materials, and multipurpose.Again, this is in sharp contrast to the modern world, where we have so many belongings it's impossible to keep track of them all. We have giant houses that we "need" to store all these things, and still it doesn't seem like enough. Many of our possessions are indispensable if we want to fit in to society. We need (or feel we need) clothes, cookware, identification, money, transportation, furniture, tools, sports gear, et cetera. Having to be responsible for this extraordinary quantity of possessions (by evolutionary standards) is a heavy weight on our minds.
Unfortunately, we have more than just possessions on our minds. To live in the modern world is to be pricked to death by a thousand small responsibilities. Remember to make your lunch. Remember to make a doctor's appointment, shop for groceries, tie your shoes, get your oil changed, send that e-mail, make dinner, go for a jog, vacuum the floor, take a shower, pick up the kids-- the list is endless. Are our memories as defective as we think they are, or are we simply not designed to keep track of so many details?
In hunter-gatherer times, we had stress. Homicide, accidents, infectious disease and predation were always stalking us. But did we have a constant flow of obligations clogging the paths of our minds?
Those times are gone for us, but perhaps keeping them in mind can help us live more constructively in the modern world. I find that meditation helps keep the thousand pricks of modern life in perspective, perhaps bringing my mind closer to the paleolithic state.
Rabu, 03 Maret 2010
Sesame Street's "Talk, Listen, Connect": A Strong Public Health Program for Military Families
Both academic and popular news sources have been reporting on the health problems experienced by active duty military and veterans (e.g., Post Traumatic Stress Disorder (PTSD) and Traumatic Brain Injury (TBI). Recently we have also begun to see research looking at the health problems experienced by spouses and children within military families. This January USA Today story highlights two such research studies:
(1) The first study (published in the New England Journal of Medicine) concluded that wives of soldiers sent to war suffered significantly higher rates of mental health issues than those whose husbands stayed home.
For example, wives of soldiers deployed to Iraq or Afghanistan between one and 11 months had an 18% higher rate of depression than those whose husbands did not go to war. When soldiers were deployed 11 months or longer, their wives had a 24% higher rate of depression.
(2) The second study (by the RAND Organization) found that children of deployed parents suffer more emotional issues, particularly if separations are long or the parent at home is troubled.
Based on this data, public health experts can see a clear need to develop interventions not just focused on active duty military and veterans, but also for their families. Therefore, I was happy to see that Sesame Workshop (the non-profit organization behind Sesame Street) has created a program called "Talk, Listen, Connect", which addresses priority issues for this population. I reviewed three brief videos and accompanying literature on this project and was very impressed:
- The "channel" being chosen to reach parents and children is an existing one. Families are already familiar with (and trusting of) Sesame Street, so they are not asking families to bring an unfamiliar resource into their homes. E.g., Elmo is the character used most frequently in these videos, and he is beloved by children. They are used to learning from Elmo.
- The videos used various methods for providing information, so it can be appropriate for learners of multiple levels/backgrounds. E.g., Pictures, songs, modeling of conversations between Elmo and his Dad, celebrity cameos (Queen Latifah stars in the third video).
- The creators obviously did research into relevant issues for military families (e.g., the videos address preparing for deployment, adjusting to homecoming, and coping with changes). The third video even shows a child coping with a Dad who came back with TBI- an injury unfortunately too common with these wars.
- The Sesame Workshop is even going beyond education to address real barriers to families staying connected. I was thrilled to see them examining challenges in the environment! They have created Sesame Street Family Connections. It is a little like having a Facebook Family Page. It is a a child-centered online space where both children and adults can interact and stay connected over long distances when everyday communication can otherwise be difficult. Family and friends can post pictures and videos, share messages and artwork, etc. This strategy is attempting to increase connections and family support (and decrease isolation)...which can help reduce associated negative health effects (e.g., depression).
- A plan for outcome evaluation exists! So often, this is left out of public health education planning. Although research about the effects of Talk, Listen, Connect on families experiencing multiple deployments and injuries is forthcoming (as the projects moves through several phases of roll-out). A summary study for the first phase of the project, which dealt with a parent’s first deployment, revealed that the materials helped military parents and children feel better during deployment, and helped them to be prepared emotionally for the deployment process. It also showed that Talk, Listen, Connect is helping parents by giving them the language and tools they need to engage in a dialogue with their children.
Senin, 01 Maret 2010
Book Review: S.P.E.E.D.
I really appreciate the abundant in-text references the authors provided. I have a hard time taking a health and nutrition book seriously that doesn't provide any basis to evaluate its statements. There are already way too many people flapping their lips out there, without providing any outside support for their statements, for me to tolerate that sort of thing. Even well-referenced books can be a pain if the references aren't in the text itself. Schoeneberger and Thiboutot provided appropriate, accessible references for nearly every major statement in the book.
Chapter one, "What is a Healthy Weight", discusses the evidence for an association between body weight and health. They note that both underweight and obesity are associated with poor health outcomes, whereas moderate overweight isn't. While I agree, I continue to maintain that being fairly lean and appropriately muscled (which doesn't necessarily mean muscular) is probably optimal. The reason that people with a body mass index (BMI) considered to be "ideal" aren't healthier on average than people who are moderately overweight may have to do with the fact that many people with an "ideal" BMI are skinny-fat, i.e. have low muscle mass and too much abdominal fat.
Chapter 2, "Sleep", discusses the importance of sleep in weight regulation and overall health. They reference some good studies and I think they make a compelling case that it's important. Chapter 3, "Psychology", details psychological strategies to motivate and plan for effective weight loss.
Chapter 4, "Exercise", provides an exercise plan for weight loss. The main message: do it! I think they give a fair overview of the different categories of exercise and their relative merits, including high-intensity intermittent training (HIIT). However, the exercise regimen they suggest is intense and will probably lead to overtraining in many people. They recommend resistance training major, multi-joint exercises, 1-3 sets to muscular failure 2-4 days a week. I've been at the higher end of that recommendation and it made my joints hurt, plus I was weaker than when I strength trained less frequently. I think the lower end of their recommendation, 1 set of each exercise to failure twice a week, is more than sufficient to meet the goal of maximizing improvements in body composition in most people. My current routine is one brief strength training session and one sprint session per week (in addition to my leisurely cycle commute), which works well for me on a cost-benefit level. However, I was stronger when I was strength training twice a week and never going to muscular failure (a la Pavel Tsatsouline).
Chapter 5, "Environment", is an interesting discussion of different factors that promote excessive calorie intake, such as the setting of the meal, the company or lack thereof, and food presentation. While they support their statements very well with evidence from scientific studies, I do have a lingering doubt about these types of studies: as far as I know, they're all based on short-term interventions. Science would be a lot easier if short-term always translated to long term, but unfortunately that's not the case. For example, studies lasting one or two weeks show that low glycemic index foods cause a reduction in calorie intake and greater feelings of fullness. However, this effect disappears in the long term, and numerous controlled trials show that low glycemic index diets have no effect on food intake, body weight or insulin sensitivity in the long term. I reviewed those studies here.
The body has homeostatic mechanisms (homeostatic = maintains the status quo) that regulate long-term energy balance. Whether short-term changes in calorie intake based on environmental cues would translate into sustained changes that would have a significant impact on body fat, I don't know. For example, if you eat a meal with your extended family at a restaurant that serves massive portions, you might eat twice as much as you would by yourself in your own home. But the question is, will your body factor that huge meal into your subsequent calorie intake and energy expenditure over the following days? The answer is clearly yes, but the degree of compensation is unclear. Since I'm not aware of any trials indicating that changing meal context can actually lead to long-term weight loss, I can't put much faith in this strategy (if you know otherwise, please link to the study in the comments).
Chapter 6, "Diet", is a very brief discussion of what to eat for weight loss. They basically recommend a low-calorie, low-carb diet focused on whole, natural foods. I think low-carbohydrate diets can be useful for some overweight people trying to lose weight, if for no other reason than the fact that they make it easier to control appetite. In addition, a subset of people respond very well to carbohydrate restriction in terms of body composition, health and well-being. The authors emphasize nutrient density, but don't really explain how to achieve it. It would have been nice to see a discussion of a few topics such as organ meats, leafy greens, dairy quality (pastured vs. conventional) and vitamin D. These may not help you lose weight, but they will help keep you healthy, particularly on a calorie-restricted diet. The authors also recommend a few energy bars, powders and supplements that I don't support. They state that they have no financial connection to the manufacturers of the products they recommend.
I'm wary of their recommendation to deliberately restrict calorie intake. Although it will clearly cause fat loss if you restrict calories enough, it's been shown to be ineffective for sustainable, long-term fat loss over and over again. The only exception is the rare person with an iron will who is able to withstand misery indefinitely. I'm going to keep an open mind on this question though. There may be a place for deliberate calorie restriction in the right context. But at this point I'm going to require some pretty solid evidence that it's effective, sustainable, and doesn't have unacceptable side effects.
The book contains a nice bonus, an appendix titled "What is Quality Evidence"? It's a brief discussion of common logical pitfalls when evaluating evidence, and I think many people could benefit from reading it.
Overall, S.P.E.E.D. was a worthwhile read, definitely superior to 95% of fat loss books. With some caveats mentioned above, I think it could be a useful resource for someone interested in fat loss.