I use a smoke detector and carbon monoxide detector when I travel. Many people have told me I am being ridiculous.

A few friends tell me it’s a good idea, but they never do it themselves. Fires and carbon monoxide poisonings while traveling are not rare. It is estimated that there are 3900 fires in hotels and motels yearly in the United States. Carbon monoxide poisonings are not as common, but they do happen, and they are preventable. I talk about risk prevention in this post.

I hope you have smoke and carbon monoxide detectors in your home. Now, think about how often you travel. I may sleep in a hotel or vacation rental about 10% of the year. I don’t trust hotel staff to make sure the smoke and carbon monoxide detectors are in working order. I trust owners of rental homes even less. We have been in good VRBO rentals where there were no CO detectors, and many bedrooms didn’t have smoke alarms. At one resort in the Florida Keys, the smoke alarm was beeping because the battery was low. I called the owner, and they told me to disconnect the detector. Why would I trust my family’s lives to people who don’t take the risks seriously?

The risks are real. Previous guests may have disconnected the alarms if the batteries needed to be replaced, and they didn’t want to be bothered. Guests in other rooms may not be as cautious about fire prevention as you are. A guest in the room next to you may be using an appliance meant for outdoor use, leading to carbon monoxide buildup.

Nothing could be simpler than preparing yourself against these emergencies. There are many smoke alarms and CO detectors designed for travel, though regular home devices should be fine. I didn’t buy this model, but mine is similar. I like the 10-year battery, even if it actually doesn’t last that long. This is not a good alarm for permanent use in your home because it is not hardwired. However, if you are traveling, it is far better than relying on the hotel or Airbnb.

Carbon monoxide is an odorless, invisible gas that can kill you in your sleep. It affects children more than adults, and prevention is simple. I have bought five of these detectors for my house and travel. It also has a ten-year battery. It has a simple on and off switch, so it doesn’t go off in your luggage. I prefer this model to the ones without a display because you can see the history of any positive readings. If I’m gone all day hiking, I can come back to the hotel and check the history. Perhaps there was a mild elevation in CO levels that wasn’t enough to cause an alarm. I want to know if that happens, so I can find the cause. The next elevation could be dangerous.

You can’t protect yourself from every risk, but lowering your risk of being caught in a fire or dying of carbon monoxide poisoning while traveling is simple. Combined, it will cost about 80 dollars and will give you years of protection and peace of mind.

I have been wary of the consumption of microplastics and have written on the topic here. I went somewhat overboard when I first looked into the harms of microplastics and wrote a second post. There is little doubt that microplastics, which form with the degradation of plastic products, can harm the environment. There is some evidence of risk to human health, but not as much evidence as I had initially thought. In animal studies and a few human studies, accumulation of microplastics in the body may increase the risk of stroke and cancer. I am not sure how much actual risk this translates to, but microplastics are definitely worth avoiding when possible.

The good news is that when food is stored in plastic containers but not heated, the degree of microplastic shedding is low. Therefore, storing food in vacuum-sealed, high-quality, food-safe plastic bags seems to be low risk. On the other hand, heating food in a plastic container results in large amounts of ingested microplastics. I try to avoid coffee cups that contain plastic (most do) and tea bags made with plastic (again, most do), but I have no problem vacuum sealing salmon and storing it in the freezer or cheese to protect it in the refrigerator.

Sous vide, even in high-quality plastic bags designed for it, worries me. For an excellent guide to sous vide and its safety, I recommend Serious Eats. Sous vide recipes call for cooking at temperatures ranging from 125 degrees to 160 degrees or higher for one to several hours. That would be expected to release microplastics. There are few direct studies on microplastics and sous vide, but many chemicals are released into the food. This is why I worry. I have hesitated to cook sous vide with plastic until this issue is resolved.

Why do I care? Well, sous vide is a superb way of cooking. If I am going to eat red meat, I want to have the option of cooking sous vide. You can cook pork (tenderloin and chops are favorites), and it always comes out perfect. It cooks at a lower temperature, so you don’t overcook it. I prefer steak reverse-sear or grilled (if my wife or son does it), but sous vide will always result in a perfectly done steak. I have also used the technique for salmon and chicken, and it is superb.

There are a few non-plastic options, mainly with silicone bags, but the reviews are generally poor. I don’t want to waste money on a silicone system that makes sous vide safer than plastic, but makes food that is not worth eating. What is the answer? Well, my son saw someone’s post online about Silivac and told me about it, knowing my reluctance to do sous vide in plastic. Silivac uses high-grade silicone bags, designed to stand up to prolonged cooking. There is no plastic in the bags.

I reviewed the safety data on these silicone bags. They are engineered by the safest method (platinum-curing, which I hadn’t heard of) and have been rigorously tested. I confess I do not understand exactly how the silicone is made, but I have read multiple safety studies. Migration of anything into food is minimal, even at higher temperatures (100 degrees Celsius/ 212 F. I assume it is not perfect because nothing is, but it releases no plastic and negligible amounts of anything into food. The safety data is available on their website. Click here and then click on “Read Our Safety Reports.”

I am satisfied that Silivac bags are safe enough to use. Remember, nothing is totally safe. You use your grill and get smoke into the food. Smoke is known to have some risks. Everyone loves the taste of food that is browned, something called the Maillard reaction, and there are some health concerns with the process. You have to enjoy life. I will eat grilled food.

I was intrigued by the website and decided to buy a starter bundle.

This is the image of the starter bundle from the Silivac website, with two bags, the vacuum machine, and two needles to insert into the bags.

PLEASE NOTE: I had never heard of Silivac until my son told me about them. He has no relationship at all with the company. I have received no money or any inducements to write this review. I bought the starter pack and an extra bag with my own money, receiving a 10% discount like anyone else could. I think the discount is still available.

I used the Silivac machine for the first time a week ago, making pork tenderloin steaks. You take a tenderloin and pound it to about an inch thick. Then, you cut the large, flattened tenderloin into two steaks. I put both into one bag and sealed it, which is just like sealing a Ziploc bag. I then removed the air with the Silivac vacuum device, and put the bag into the water. If you are interested, I used this recipe for the steaks. I subscribe to America’s Test Kitchen (ATK) and am not paid anything by the company.

The photo below shows the bag on the left and the tenderloin steaks on the right. Please note that the salt is Morton’s Lite Salt, which has been shown to lower blood pressure. Also, because of possible cross-contamination, I put the dish towel in the washing machine.

The company is hoping to soon make larger bags, and I intend to buy one, but the steaks fit in one bag easily. The machine was simple to use, and I have a picture below.

This is my set-up, with the sealed bag in the water. The machine is an Anova. The container is Everie, though you can use a deep pot. Later in the post, I will show you how the Silivac machine works.

Below is a photo of the pork after it finished cooking. As you will see from sous vide recipes online, to make it taste better and to make it look more appealing, you dry the surfaces of the pork and sear it on the stove, grill, or broiler.

ATK uses a freezer bag in their recipe. To do so, you use a water replacement technique that helps remove all the air from the bag as you put it in the water. Of course, I don’t like to do that because of the microplastics. The Silivac bags have two seals with an air compartment in between. It is simple to remove all the air. Much easier than the Ziploc technique. Silivac bags have two seals. You seal the outer one, attach a needle to the vacuum, and insert it in a hole on the side of the bag. Turn on the machine, and when the air is all gone, close the inner seal and remove the needle. The sous vide cooking is just how you would do it with a Ziploc bag or vacuum sealer with a plastic bag.

The following week, I made pork chops. They turned out perfectly. After cooking, I dried the chops and seared them in a cast-iron skillet on the stove. Read the recipe’s instructions to avoid overcooking the pork or setting off the smoke alarm.

The next images show me adding a pork chop to the Silivac bag, attaching the device via a metal needle, and the pork chop inside the vacuum-sealed bag.

Recipes come with recommended times and temperatures. I cook pork chops for 90 minutes, starting when the water reaches and holds at the temperature I want. Just like cooking in an oven or on a grill, the length of time and temperature you cook at will affect how done the meat is, but it is difficult to overcook meat using sous vide. Below is a photo of the meat at the end of immersion cooking. testtttt

Conclusions

• Silivac bags shed no microplastics.
• I have no concerns regarding the safety of the system, provided you follow the recommendations of a reputable cooking recipe.
• The bags are made of high-grade silicone and should last a long time.
• The system is easy to use.
• The vacuum seal was equivalent to vacuum sealing with plastic and much simpler. It is a clear step up from Ziploc bags.
• The food came out as good as I have made with any method of sous vide. There were unexpected benefits. I messed up the sealing once and simply unsealed the bag and resealed it in a matter of seconds. If you mess up with a plastic vacuum seal, you generally have to throw away the bag. The Silivac system avoids a problem with plastic vacuum sealers. They seal the bag with heat, melting the plastic. That works poorly if there is liquid at the edges of the bag. Also, when you use a vacuum sealer with plastic, it uses a higher pressure and compresses the meat more. This can force contaminated liquid into parts of the machine that are difficult to clean, causing a risk of infection. Silivac bags can seal even if they are wet, and in the small chance liquid gets into the machine, it would be simple to clean. Finally, it is easy to unseal the bag when you are finished cooking.

I am very pleased with the Silivac system and intend to use it for all my sous Vide cooking.

Screening for Coronary Disease is not what most people think.

Coronary artery disease is the most common cause of death in the United States and the world. Briefly, when someone has a heart attack, it is due to coronary disease. Cholesterol plaques are deposited in the lining of the coronary arteries, which deliver blood to the heart itself. This causes inflammation and damage to the arteries, and clots can form. When the clot occludes the flow of blood, a heart attack can occur, causing damage to the heart muscle and sometimes dangerous and fatal heart rhythms. Even if complete occlusion doesn’t happen, narrowing of the arteries can cause chest pain and weakness of the muscle, leading to heart failure.

Unfortunately, many people have no idea that they have coronary disease until damage is done. Sometimes, the first sign of the disease is sudden death from a heart attack or arrhythmia. Like most conditions, we would like to diagnose coronary disease early, while there is time to prevent the dangerous signs and symptoms.

Most people do not know what it means to screen for coronary disease. They think that the doctor listens to their heart, checks their cholesterol, and they’re good to go. That is not what I’m talking about. Listening to the heart does not detect early or even late coronary disease in most cases. Checking cholesterol levels is extremely important, but cholesterol levels are a risk factor for heart disease, not heart disease itself. There are many risk factors for coronary disease: cholesterol levels, diet, smoking history, family history, body weight, body fat distribution, and others. Even if you have multiple risk factors, you may never develop the disease, and some people with coronary disease have few if any risk factors.

Sidenote: I have heard people say many things about cholesterol. One is that they don’t understand how they had a heart attack since their cholesterol is fine. A similar statement is that they aren’t going to have a heart attack because they have normal cholesterol levels. Elevated cholesterol is a risk factor for heart disease, and treatment to lower cholesterol lowers the risk of heart disease. (This is definitely true, and anyone who says otherwise is mistaken or lying.) But people can have heart disease without having an elevated cholesterol. Risk factors are just that.

This is true with many conditions. Family history of breast cancer is a risk factor for breast cancer, but most women with breast cancer have no family history. Many people involved in serious car accidents are good drivers with a spotless record and no prior history of accidents. While most cases of lung cancer are in smokers, not all are. During my career in medicine, I saw many, many cases of coronary disease in people who did not expect it.

So, how do we screen? A person’s risk of a disease affects how we screen for it. For example, a teenager has an exceedingly low risk of prostate cancer, so we don’t screen at all. The same is true for breast cancer. Most young women should not be screened for breast cancer. People at very low risk don’t need screening. People who already have proven coronary disease need testing, but not the screening tests that we are going to talk about.

Let’s look at specific types of people. First would be people who are at very low risk and should not get screened. Tests are not perfect. Since a young, healthy person with no risk factors for heart disease (no family history of disease at a young age, and no genetic cholesterol problem) has such a low risk, false positive tests would actually outnumber any positive tests that were real.

We often screen people without symptoms who want to start an exercise program. They or their doctor may want to make sure they are safe to participate. A stress test may be a good choice. The patient walks on a treadmill in a standardized, progressively more difficult protocol, while an ECG is running. Sometimes, an ultrasound (echocardiogram) or nuclear imaging test is also performed. Certain changes on the ECG or imaging would indicate an increased risk of the patient having diseased, narrowed arteries. Further testing, such as a coronary angiogram, would then be performed to determine the extent of disease and whether treatment is indicated.

People with no symptoms but who are at significantly elevated risk may not need screening. They are so likely to have coronary disease that the doctor could just assume that they do have it. For example, they may have a markedly elevated LDL cholesterol and multiple family members with coronary disease. Aggressive risk factor modification would be instituted without further testing. This includes good blood pressure control, cholesterol-lowering medication (typically a statin such as rosuvastatin, which I take), and an exercise program. A stress test might be performed, as mentioned above, to see if they can tolerate such a program.

Perhaps the most common type of patient to screen is one where the risk of disease is intermediate. They may have a family history, but the cholesterol is not markedly elevated. A smoker without a family history may fit in this category. Here, a stress test would not be good enough. Remember, a stress test only detects advanced disease. A routine ECG would be of little help and is not recommended to screen for coronary disease, because there are many false positives and negatives. In this patient, a coronary artery calcium scan may be best, and it was the test I preferred when I was in practice.

The scan itself is simple. You lie in a machine for a few minutes. It is not enclosed like an MRI, and I have never heard of anyone becoming claustrophobic. There are no injections and essentially no risk. When cholesterol plaque is deposited, it is soft and uncalcified. Over time, the plaque calcifies, and you can see it on the scan. You will get a numerical score reflecting how much calcium is found in the lining of the arteries. The best is zero. That means that you have no detectable calcification in the coronary arteries. The percentile tells you how you compare to others your age.

A low score when you are young may be in a high percentile. That same score when you are older will put you in a lower percentile. If you are under 50, most people have a zero score. That could be because there is no plaque, but it could also mean that it is there but hasn’t calcified yet. Some specialists would recommend repeating the scan every five years or so until you are 60, giving the plaque time to become visible.

The calcium score scan doesn’t tell you if the arteries are narrowed, though the higher the score, the more likely it is that there is some narrowing. Even without narrowing, plaque can cause a heart attack, but narrowing makes heart attacks more likely. If your doctor suspects narrowing, they may order a stress test or a CT angiogram, a more detailed scan that shows narrowing. The CT angiogram is more expensive than the calcium scoring and requires injection of a contrast agent and more time in the scanner. The CT angiogram is not an appropriate screening tool for most people.

I found the calcium score test to be very helpful. For example, if you are 50, one of your parents had a heart attack in their 50s, but your cholesterol is fine, and you have no other risk factors for heart disease. You might consider a scan. If there is no plaque, your doctor may just repeat the scan in five years. If there is plaque, they may recommend a change in diet and start a statin to slow or prevent further plaque deposition. Statins reduce the risk of a heart attack and save lives.

Everyone wants to have a longer, healthier life, but we all want to live life to the fullest. Many people watch their diet and exercise, but otherwise ignore their risk of the most common cause of death. Talk to your doctor about screening for heart disease. Maybe you haven’t reached the age where any specific screening is needed. If screening is considered, ask if a calcium score is a good idea.

Diminishing Returns are defined by Webster as “benefits that, beyond a certain point, fail to increase in proportion to extended efforts.”

Diminishing returns, sometimes called the Law of Diminishing Returns, often refer to businesses. For example, as a company increases the number of employees (labor), its productivity increases. After a while, the increase in benefits slows down—adding new employees doesn’t help as much as it used to. Eventually, the company will lose money if it continues to increase labor costs above a certain amount. I apply this law to health.

Look at this chart:

Along the bottom is the effort you put into a healthy habit. Let’s say aerobic exercise. On the left, going vertically, is the impact that exercise has on your health: on weight loss, heart attack risk, and a multitude of other issues. If you are at zero effort, meaning you don’t exercise at all, there is no impact, of course. As you put in more effort exercising and move along the curve to the right, the impact increases and your health gets better. When your effort reaches five or so on my chart, but every healthy habit is different for every individual, the increase in benefit diminishes. To clarify further, for each increase in exercise, you get less of an improvement in your health. It still improves, just not as much.

Here is a real-world example. As I said in a prior post, a key to good health is to concentrate on the big things first. Exercise is a big thing. Say you never exercise at all, and you start walking a mile, three days a week. As you increase to 7 days a week, your cardiovascular health improves significantly. You are on the left part of the curve, which we call the steep part of the curve. If you get in better shape and switch to running a few days a week, your health improves further, at a good rate. If after a year of working out, you’re running six days a week for three miles, you are probably at five or six on the graph, and the curve starts to flatten. If you increase how much you run, the benefits you see will not increase as much or as fast as when you started. That is the law of diminishing returns. Eventually, even with more effort, the benefits may not increase at all. This is called a plateau. Running six miles a day, six days a week is not much better than five miles a day. See my book for more details on the benefits of exercise.

The same law applies to the weight loss that follows as you improve your diet by cutting calories, cutting carbs, or, in my recommendation, getting rid of the bad carbs that hinder weight loss. When you cut back on enough calories or bad carbs, you lose weight. As you cut back more and more, you lose weight faster. Eventually, you may reach a level of cutting where the rate of weight loss slows down. You may still be losing weight, but not as fast. This happens more with cutting calories than bad carbs, but it can happen with any diet, even the new GLP-1 medications and bariatric surgery. If you use the diet I recommend, The Three Rules to Lose Weight and Keep It Off Forever, it usually doesn’t reach the plateau where weight loss stops until you reach your goal.

Sometimes, if you keep increasing whatever you are doing, you may start to make something worse. You know this intuitively because it’s true for many things. Sometimes, after the plateau, negatives occur. Adding salt to food is an obvious example. If there isn’t enough salt, adding salt makes it taste better. But too much salt will ruin the dish. This is the best portrayal I have seen.

This happens with many healthy habits. Cutting calories too much leads to malnutrition, and running too much can be dangerous. Most vitamins and supplements have diminishing returns at a fairly low level, and a plateau is quickly reached. After the plateau, if you keep increasing, even some vitamins can become toxic, including vitamins D and A. As you know, this often happens with medications, and the toxic dose varies for different medications. I am on a relatively low dose of a blood pressure medication. If I doubled the dose, I would probably have side effects. With medications and supplements, the problem is easily avoided by reading labels and checking with your doctor.

An important problem with diminishing returns is that you think you’re helping things by increasing efforts with one healthy habit, ignoring others where you could improve and make a difference. Many weightlifters keep increasing their efforts and ignore diet and cardiovascular exercise. Others take every supplement ever invented and don’t eat healthy or exercise. You can spend a lot of money eliminating more and more plastics from your diet and forget about losing weight. Some will read every label to eat only organic and non-GMOA and not work on their weight. You have to be aware of where your efforts fall on the curve above, and that may require consulting a medical source.

Ignoring the law of diminishing returns sometimes distracts us from things we could do for our happiness and well-being. Taking reasonable protection against infections is wise, but isolating yourself from others leads to loneliness and depression. Instead of exercising so much, I could spend more time with my family. I could also practice meditation or develop other habits that would help my mental health. Despite what some people say, butter and red meat have health risks. Working hard and cutting red meat and butter to twice a month can be helpful, especially if you’re at increased risk of heart disease. Cutting further to zero has no proven benefit. I like eating red meat and foods with butter in them, and will not eliminate them from my diet for no benefit.

I strongly recommend working on healthy habits and concentrating on the part of the curve that is to the left of the diminishing returns zone. A good guide is my book, The Six Rules for a Longer, Healthier Life. Now, there is one more thing I want to mention.

Keep in mind a very important concept: The Threshold Effect.

The threshold effect is when you attain little or no benefit until you reach a level of effort or change. This is extremely important if you are on a low-glycemic diet, such as The Three Rules to Lose Weight and Keep It Off Forever, or a low-carb diet like the Atkins Diet (similar to Keto), but it’s seen to some degree on a low-calorie diet. As you start to cut back on bad carbs or calories, you may not initially notice substantial weight loss, though some do. As you increase your efforts, the amount you lose on a weekly basis will increase rapidly. If you give up all bad carbs, as I usually recommend, you will definitely have crossed the threshold and will lose a substantial amount of weight every week. Eventually, you may eventually reach a plateau, usually when you’re at the weight level you want to be.

See the graph. You may not notice much, if any, weight loss until you reach the threshold. In my graph, I arbitrarily started the weight loss at about 2.5 units of effort. That might be eliminating 90% of bad carbs or cutting calories by a few hundred a day.

When you reach 2.5, you lose weight faster and faster until you get diminishing returns. You lose weight, but each time you cut calories or bad carbs, the weight loss diminishes. Eventually, you may reach a plateau.

A common mistake is to forget the Threshold Effect if you cut back on your efforts. You may expect to have continued success when you slack off a bit, because you are eating fewer bad carbs than when you started. Perhaps you started eating one or two cookies a day or a few pieces of bread a week. However, if you slack off enough, you will reach the threshold in reverse, and you are likely to stop losing weight and even gain weight. I have made that mistake too many times to count.

The threshold for weight loss can be very high for some people. To lose weight, some need to get below 1200 calories a day. On keto, they need to be below 20 grams of carbs a day, and on a low-glycemic diet, you may need to give up all or nearly all bad carbs. Fortunately, you can otherwise eat what you want and should never be hungry.

Cutting calories has an additional problem—tolerance. Your body becomes accustomed to the lower calorie intake. If you start at 2000 calories, your threshold for weight loss might be 1600 calories a day. But, if you eat that amount, you will see diminishing returns quickly, so that you lose none or virtually none after a month. You’ve reset the threshold. Now, if you go back to 2000 calories, you will gain weight when before you had been stable at that level.

Keep in mind where you are on the curves above. Push hard enough to cross a threshold, and be especially careful not to cross that threshold in reverse if you back off on your efforts. Additionally, if you have reached the level of diminishing returns, don’t continue to increase your efforts at the expense of another healthy habit you could work on.